There are plenty of them in the road today with 150k+ miles and maintaining double digit resale value. The same can't be said for the Ford flathead V8. Did any even make it to 150k miles?

I think most complaints are based around the comparatively high labor costs of today. That isn't exactly an engineering problem.

Tug, I know this isn't exactly what you meant, but...



Here's the website I took this from:

https://www.fordbarn.com/forum/showthread.php?t=17...

That being said, this item at least provides anecdotal support for your claim:



And this it the site this item was taken from:

https://www.fordbarn.com/forum/showthread.php?t=20...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

I suppose it is about cost, but then again, most long life engines are used much more than what is in your car/truck. The difference maybe that your car/truck sits most of the time, and is suddenly asked to perform.

I would still tend to think 'keep it as simple as possible, and no simpler' is better. Adding more parts to manage exhaust is not keeping it simple, and is likely a big part of the automotive issues. Also short life parts used in more modern cars, like plastics, computers, etc.

Eh, I've owned several 3Vs and would consider another. They're one of the most popular recent engines sold, several million produced annually for two decades. Spend ~$2k to have the phasers replaced with OE parts ~150k and you're done aside from standard maintenance and annoyances.

FCA's 5.7 hemi- a common failure is wiping off one or more cam lobes, looks like after about 80K miles you are in the "danger zone". I figure that was the reason FCA shortened their powertrain warranty from 100K to 60K miles.

What is a phaser? In this discussion.

Would it perhaps be a cam follower? If so, why the name change?


spsalso

Camshaft phasers advance and retard the timing of the cams to operate on different cycles or to alter lobe separation angle. LSA determines what rpm range the engine makes best power at. Delaying intake valve closure is key to the Miller and Atkinson cycles.

Thank you.

spsalso

enginesrus. you mentioned the 3.0 Duramax in that other thread. Could you elaborate please?

The problem with sloppy work is that the supply FAR EXCEEDS the demand

Quote (enginesrus)

This guy explains. Has data from others that deal with the same problems.

How much data?

What's the real failure rate?

What's the failure rate within the warranty period?

How does this compare to historical failure rates for similar engines in similar use cases?

What's the failure rate associated with insufficient maintentance?

You don't know.

Food for thought though- Ford produced nearly 20 million 5.4L Tritons over the 20 year production run of this specific variant. 20 million. So what's the real failure rate?

The Mercedes OM616 and OM617 diesel engines lasted far longer than the California Air Resources Board would have liked. They met EPA and california emissions NOx standards in the 70's and 80's, of 2 gm/km, which is about 10x a dieselgate VW on a bad day.

SnTMan (Mechanical)
5 May 22 14:04
enginesrus. you mentioned the 3.0 Duramax in that other thread. Could you elaborate please?
--------------------------------------------------------------------------------------
The use of timing chains, and a rubber (not sure of the material) belt that drives the oil pump. All at the flywheel end.
Just bad choices. Maybe lasting to the end of the warranty period. As always cutting corners and cheap/ inexpensive to build.

enginesrus, bear with me please. The belt I get, but timing chains are very common. What would you propose instead?

The problem with sloppy work is that the supply FAR EXCEEDS the demand

Timing rollers.


https://adsabs.harvard.edu/full/1979JBAA...90...45...

Much smoother and more precise.

And this used in engines as opposed to timing chains, gears, shafts etc? Again, pardon my ignorance...

The problem with sloppy work is that the supply FAR EXCEEDS the demand

We had a 1997 Cadillac Catera, which was basically a re-badged, pimped-out Opel Omega, imported from Germany. It was a great car in terms of handling and braking, however, it was a bit under-powered as the 'Americanized' version was 500 lbs heavier (more insulation and interior appointments) plus the automatic transmission and air conditioning. Anyway, we had it about two years when one day, as I was driving, the engine just seized-up cold, right in the middle of an intersection. Luckily, no one ran into me, but I couldn't move the car an inch, as the engine had frozen. I had AAA take it the dealer and they gave us a loaner (a big new Cadillac DeVille). It turned out that an idler pulley on the serpentine accessory belt disintegrated. It was a steel pulley, with what looked like a urethane cover on the pulley face, and this 'cover' peeled-off causing the belt to come loose. Now if that was all that had happened, it wouldn't have been a big deal, however, the overhead valve trains were driven by a timing-belt. Now this was a V6 engine and each bank of valves had it's own belt system, which was under a plastic cover which was supposed to keep them protected, however, it was open on the bottom and when that accessory belt failed, a section of it snagged one of the timing belts from under the cover causing it to break, which of course meant that one bank of valves stopped moving while the engine was still turning over. This smashed the tops of at least one piston and messed up a couple of valves (this was a four-valves per cylinder scheme). The dealer had the car for better than a month while they rebuilt the engine.

A couple of months later, we got a recall notice from GM covering this exact issue with the idler pulley. It seems that Opel had been using this design for a couple of years in Europe without any problems, but apparently after a couple of years in the hot, dry conditions of Southern California, this caused that 'urethane' cover to come loose and fall off. Now most of the time, it just caused the accessory belt to fail, but in about 10% of the cases, it ended up like what happened with our car.

Then in 2000, Cadillac decided that, even though our car had already been fixed with a properly designed idler pulley, they decided to make good on the cars that had had the seized engines, replacing our 1997 Catera with new 2000 model, at no additional cost. We drove that car for about three years, before selling it.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Toyota, who's reputation is built on reliability, isn't doing themselves any favors rebadging a BMW as their Supra.

SnTMan (Mechanical)
5 May 22 23:42
enginesrus, bear with me please. The belt I get, but timing chains are very common. What would you propose instead?
---------------------------------------------------------------------------------------------------------------

I'll answer the question with a question.
What has been used for years to connect the camshaft to the crankshaft? It is a history lesson.
And start the study with the Fair Banks Morse OP engines, that is even more demanding of an Engine crankshaft drive connection.
Then move on to the older NT Cummins truck engines, Caterpillar truck and equipment engines, Detroit Diesel 71 Series, EMD 645 Engines, the early 50's Chevrolet 235 and before that date models, I could go on.
Yes timing chains common on I'll designed junk, not made to last, study the BMW fiasco, https://www.carcomplaints.com/news/2020/bmw-timing... .
Chains stretch, and can cause OBD Codes, the fix is a huge cost, especially if valves hit pistons etc. etc..

If you want to use timing chains on an engine that you want to last, you must choose/specify components that will deliver that.

If you want to build/sell crap, don't bother.


spsalso

I don't know of many mechanical items that use chains that have a long life time. And that is the key words used. "IF YOU WANT TO USE" In designing something to be durable it is not a case of "if you want to use" its a case of, use the correct system or method that has been proven to last. I gave engine examples where a timing chain would never have been considered, why? I also give an example of the result of supposed components that were suppose to deliver, as stated in the above post. The ones cited, likely don't want to build or sell crap. The manufacture likely spent a huge sum of money to arrive at those components. In the end it is a design that will fail and is why you will not find a timing chain on an engine like in this video, it is really that simple. https://www.youtube.com/watch?v=hMqZet0Lj9I

So gear drive I'd say

The problem with sloppy work is that the supply FAR EXCEEDS the demand

So having a timing chain/belt is an engineering failure??

Just because some timing chain designs wear prematurely doesn't condemn the entire concept.

Gotta go. I have to drive to work in a car powered by a Fiat 1.4 MultiAir with a timing belt driven OHC 16 valve engine that has just short of 230,000 km on it.

Kia is dealing with failing piston bearings. Their response is to reprogram the knock sensor to detect vibrations from bad bearings. If it detects the vibration, it limits the engine to 2000 rpm so you can limp to safety. It's a clever bit of engineering, I think, but I'd rather have good bearings.

My glass has a v/c ratio of 0.5

Maybe the tyranny of Murphy is the penalty for hubris. - http://xkcd.com/319/

The mercedes OM61x and OM60x engines use a single timing chain

My W211 Merc engine had a chain. 6 cylinder 3ltr common rail CDI

300k km without a change when it got scrapped due rust. Engine was still sweet no drop in compression over the 6 years and 120k km I put on it

Quote (TugboatEng)

Toyota, who's reputation is built on reliability, isn't doing themselves any favors rebadging a BMW as their Supra.

It is my impression that they did considerable modifications to the engine that made its way into the Supra specifically for reliability (if that's what you are concerned about).

Quote (BrianPetersen)

So having a timing chain/belt is an engineering failure??

Why is anyone still engaging in this guy's threads

This is how it goes every single time.

Entertainment to poke fun at luddites.

My engineering failure successfully got me to a job site, and back to the office, despite the pretty big number on the odometer. Nothing bad happened.

An excellent book on engine development during WWII is The Secret Horsepower Race by Calum Douglas. Very buggy Napier Sabres made into service because the British needed aircraft that could catch Fw-190s. Calem Douglas is an engineer and engine designer, so he understands the subject.

Another author on WWII engines, Bill Gunston, points out that all the important engines of WWII, were flying prior to the war. Some good aircraft were developed very quickly, but good engines take years. Douglas argues that Rolls Royce and Pratt and Whitney were successful during the war because they designed engines that were absolutely conventional, they debugged them quickly, and they spent the war souping them up.

--
JHG

I had a European sports car that had a four cylinder engine with an overhead cam shaft. The cam shaft was driven with a timing belt and the camshaft also was connected to the power steering pump. Very funny feeling when you lose both drive power and power steering. Luckily that engineer was very easy to work on.


On a more modern note, the engine used in late model Ford Fusion sedans has/had a heating problem which would damage the head gasket. There is currently a factory recall on that issue.

BiPolar, the funny part about BMW's engine problems is that they are for the most part very good engines. It's everything they attach to them that fails, plus the oil seals. I think their issues are mostly supplier related. Substitute a plastic resin or rubber type here and there and they have components that fail such as plastic water pumps/pipes and timing chain guides. Toyota has success used plastic parts on their engines but BMW seems to struggle. If BMW is building these engines for Toyota I suspect Toyota is going to inherent the BMW problems regardless of improvements made.

Sounds like the merc engine fine but everything around it rusts to death.

SwinnyGG (Mechanical)
Why is anyone still engaging in this guy's threads

This is how it goes every single time.
-------------------------------------------------------

The threads are meant to point out problems.
Why not just talk the technical and not the Personal about a person posting something here?

---------------------------------------------------
drawoh (Mechanical)
6 May 22 16:33
An excellent book on engine development during WWII is The Secret Horsepower Race by Calum Douglas. Very buggy Napier Sabres made into service because the British needed aircraft that could catch Fw-190s. Calem Douglas is an engineer and engine designer, so he understands the subject.
---------------------------------------------------
Yes great examples of excellent engineering, No timing chains there. The use of flammable metal in some of the engine parts though was not good idea for an engine in an aircraft(USA engines). Calum shows how those German engine builders did the best they could with the lack of proper materials.
----------------------------------------------------

Quote (BrianPetersen)
So having a timing chain/belt is an engineering failure??
--------------
The people that assemble the product didn't design that system so, yes.
Just ask the people that purchased the product and had to deal with such
on a vehicle that they thought would last longer. Some have paid
10 times or more what a house would have cost in the late 50's for those vehicles.
The design is the cheap alternative to what would be a proper design. But of course
those savings are not past on to the consumer.
Many times the supposed cost savings by using an incorrect design ends up costing way more
than using the correct design. Use the example posted above or think Takata airbag.
The list could go on.

As evidenced by leaking seals. brittle plastic, and biodegradable wire insulation the Germans are still doing the best they can with a lack of proper materials.

Speaking of an engine failure, the BMW N54 engine has my favorite. They used a NBR o-ring on the oil filter housing. This specific material has a very short life at engine temperatures and quickly loses resilience. This results in a leak from the oil filter housing which wets the serpentine belt. The serpentine belt is made from EPDM rubber which is actually quite a good choice for this application provided you can keep it from getting oily. Once oiled, the belt very quickly starts to degrade and shed it's reinforcement. Nothing too unique here yet BUT... The reinforcement cord pumps it's way through the crankshaft front seal and in to the oil pan where it clogs the anti-vortex strainer on the oil pump. This then starves the engine for oil, destroying it.

I would be plenty annoyed that the oil filter was in a position to leak onto the serpentine belt in the first place--no normal mechanic is fastidious enough to keep that belt clean during an oil change regardless of the leaky o-ring that would be replaced concurrently.

Griping about timing chains is a new one for me, I thought I'd heard it all but apparently not. Usually when folks gripe about the timing set its bc they have to spend the time and money to have a timing belt replaced as routine maintenance, or bc their engine was destroyed by a broken belt. Timing chain failures are extremely rare and I'd be surprised if any OE's were over 1%. Comparing either to a gear drive is meaningless simply bc there arent many (if any) production gear drives used in the light-duty market, and comparing light vs heavy-duty engines is apples and oranges. Most of my career as a tradesmen and a half my engineering ccareer was in HD engine work tho and anecdotally I can attest that gear drives do fail spectacularly.

Honda has built some motorcycles with gear driven cams. They howl! Very long gear train to the top of the engine.

Not aware of reliability being a factor.

And yes, I know, pushrods. No thanks. Not in that application.

I don't know if I'm remembering this correctly, but I recall talking to a cab driver, decades back, and he was talking about an 'L' shaped engine, as I recall. I don't remember who manufactured it, but I understood it was one of the longest lasting car engines made. Is this myth? or incorrect?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik

An 'L-shaped' engine generally meant that the intake and exhaust manifolds were both mounted on the same side of an inline engine's block. It was a rather common arrangement for larger straight-six and straight-eight engines.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

L-head as I know it is the old flat head or side valve engine.

Thanks, my memory of it is very 'fuzzy'...too many non-prescription...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik

L engine also refers to inline. People really fawn over the Ford 300 and Cummins inline-6. They attribute their longevity to extra main bearings per cylinder.

L head is flat head, F head valve in head. Even single cylinder engines carry that designation.
I don't know of too many bad designed L head engines, continental built them into the 70's as far as I know, they run just great, even when at the point of needing a major overhaul.
It is an I (eye) designation, short for INLINE, that specifies the inline engines, not an L.


Question of the day: The famous Chevrolet small block, what was a common problem at around the 100,000 mile point?

The Europeans use L to describe an inline engine. Cylinder #1 is also on the power take off or flywheel end of the engine. As the other poster mentioned cab driver maybe English wasn't a first language.

Overhead valve came to prominence in order to increase the power output of engines. If one were to operate an overhead valve engine at flathead power levels the OHV engine may last longer still. Imagine your 302 Ford rated at 80 horsepower.

Yeah in the us even most older piston aircraft engines of the airliner sort, cylinder 1 is at the rear or anti power take off end, similar to most other engines here.

the 2.7 TDV6 Land Rover Engine seems to spend more time in the garage than on the road.

Thankfully after years of fixing landrovers I have never felt the urge to get one.

Alistair_Heaton, you've doubtless heard the saying; "Land Rover. Making mechanics out of drivers since 1948". LOL

The problem with sloppy work is that the supply FAR EXCEEDS the demand

The old ones were exceptionally easy to fix. I am talking series 2 and 3 land rovers.

Lucas was known crap but the heavy mechanics was easy. The current models are nuts.

No first hand experience here. But a neighbor lady of a certain type, lives with her mother, drove a couple different model Range Rovers. Not unusual too see them depart on a roll-back. She finally gave up on them and got, uh, the Jag SUV, diesel...

The problem with sloppy work is that the supply FAR EXCEEDS the demand

The traditional American pushrod V8 engines - it wasn't just the Chevrolet small-block! - often had timing chain issues later in life. But, all of those engine designs have design origins in the 1950s and 1960s. and back then, the expected service life of an engine was much, much less than it is now.

Those engines lacked guides and tensioners for the chain. The sprockets had fixed center distances. The chain was allowed to flop around (relatively) loosely.

The GM LS engines have guides and tensioners. The modern Ford V8 engines use overhead camshafts, and guides and tensioners. The modern Chrysler Hemi has guides and tensioners.

The absence of guides and tensioners in the original American pushrod engine designs presumably gave durability that was in line for expectations in the era in which they were designed.

The newer ones are better.

I am familiar with all the old late 40's through 60's engines of all makes I worked on most all of them. And yes the timing chain was always a main failure point, especially if they used the nylon or what ever the material was for the cam gear.
The thing that lowered life in those 50's days was, the oils not so great, the road draft tube not so great. And no when the chains were new they had almost no flop. Guides are a bad thing.
As long as they weren't goofing around with phenolic or plastic for the cam gear, never saw a timing gear failure.

This is a question of why. Colorado 3.7 Atlas 5 Cylinder Engine, what was the reasoning for this engine? All the added balance shafting etc. why not just go with a nice inline 6 cylinder that doesn't need the added drive system and bearings etc. etc. ?

Timing chain guides are a GOOD thing in that they avoid the chain whipping around. The newer engines with chains that are properly guided and tensioned have less trouble with this than the old ones that didn't have it.

The Atlas series of engines had 4, 5, and 6 cylinder variants which shared many internal components. Pistons, valves, con-rods, and all related components were all the same. There's nothing wrong with modular design.

this new car i am getting as a very strange timing belt.

https://www.youtube.com/watch?v=e0FAMMvWpBQ

What do you think? You have to change it every 80k km.

Quote (enginesrus)

The threads are meant to point out problems.
Why not just talk the technical and not the Personal about a person posting something here?

It isn't personal. I know very little about you personally.

What I do know is that you don't actually have a clue what you're talking about.

'Talking the technical' would involve data. You have none. You post the exact same 'they did it better in the 40s' thread about once a week it seems in various forums, and you never have any data. Ever. Your idea of proving something is bad is 'I saw one break once and it came into my garage and now I hate it'.

This is an engineering forum. Full of engineers. Our entire lives are dedicated to the dispassionate evaluation of data- if you had some we'd all likely be quite pleased to evaluate it.. but you never do. Your entire personality on this forum is based on proclaiming that all modern engineers are idiots and that you know better.

I don't know why all these other people wast a second of their time in these threads. To be completely honest, I don't know why I do either. Probably because your 'additions' bring the overall quality of this forum down, and that bothers me.

Quote (Alistair)

this new car i am getting as a very strange timing belt.

https://www.youtube.com/watch?v=e0FAMMvWpBQ

What do you think? You have to change it every 80k km.

That engine uses a timing chain. Are you thinking about the serpentine belt? That's external, and easy to replace.

No that chain has to be swapped out.

Just it doesn't look like any timing chain I have done before

Not saying there is anything wrong with it just haven't seen the like before.

Smaller long timing chains for OHC don't seem to last better than the shorter heavier GM small block or LS chains despite the "flopping". And lots of LS did not have guides and I don't believe any had actual tensioners, just fixed or spring loaded guides. The only time they had issues was that plastic tooth cam gear used for a while 40 odd years ago. You'd be hard pressed to find many examples of later small block or LS chain failure on engines with less than 250k miles. Yet lots of plastic guide blocks on OHC stuff are worn out by then.

That type of chain is called a "silent chain". That is the same of chain used in the first generation small block Chevy engines.

I've got two old Nissan pickups, both 4 bangers.
The 94 has a single row timing chain with some really long, slender cast iron guide/ tensioner elements. At ~170 k it swallowed some fractured pieces of same. Some pieces went into the oil pan where they remain today. I'm careful to avoid negative G's :)

Meanwhile the 84 with a double row chain has no problems at 250 k. The better designed, built of the two in many ways.

The problem with sloppy work is that the supply FAR EXCEEDS the demand

BrianPetersen (Mechanical)
8 May 22 03:08
Timing chain guides are a GOOD thing in that they avoid the chain whipping around.
----------------------------------------------------------------
Problem is many of them seem to fail. Pulleys like used on timing belt applications would be a better though more expensive choice, to stop the whipping around.

Honda, in the '60's, used a chain to run the overhead camshaft on their twin cylinder motorcycle engines. It's interesting that there was a take-up roller for the chain. To adjust the take-up roller, you undid a bolt and a spring would shove the roller into the chain. Then you tightened the bolt, taking the spring back out of the system. The bolt was external on the engine.

spsalso

Yes, I had two 305 Honda Superhawk motorcycles, a 1965 and a 1968 model. And yes, that's how they kept the camshaft chain tight:



This is the 1965 Superhawk, after I rebuilt and painted it Candyapple Blue (this was the bike I owned when we got married and I was forced to buy a car as my soon-to-be wife refused to go on a honeymoon on the back of a bike):


June 1967 (Kodak Brownie Twin 20)

And this is the 1968 Superhawk that I rebuilt and painted, only this time I only used the gold Candyapple undercoat and then the clear top coat, skipping the color coat:


April 1974 (Minolta SRT-101)

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

JohnRBaker - nice Superhawk! It is of the era of motorcycles that used the cylinders and engine cases as structural frame components - who needs a front down tube!

The Honda CB750 used a cam chain follower - it had the same spring loaded thing where you'd loosen a lock bolt to let it adjust, then re-tighten.
re the mentioned engine above - 80k km seems like an absurdly short lifespan for a cam chain. I wonder if that is a misquote or a misunderstanding?
Yeah, overall I'd rather have a timing chain than a belt, I am sure the chain is not as quiet and a bit more costly, but...
And on the topic of engines good and bad - while I had great luck with GM/Buick V6, both 3.8, 3300, and 3800, my current car and its predecessor have the Chev 3.6.
DOHC, vvt, and lots of scary cam chains. I understand it is 8-12 shop hours to swap the timing chains.
But they last well over 150k miles given at least casual oil changes, and run great. (well, my first had over 150k when it got totaled, its replacement has only 120k miles)
So far so good...



Jay Maechtlen
http://www.laserpubs.com/techcomm

and that 'wizard' that whines about the Triton 3v - how about you flush the dang thing out, replace the parts that are actually bad, and run the sucker?
And his usual customers will probably keep them maintained, so the issue will probably not recurr.
I wonder if you could connect an oil supply at the oil filter mount, and pump solvent then oil through the system to clean it out?

Jay Maechtlen
http://www.laserpubs.com/techcomm

Quote (Brian Malone)

JohnRBaker - nice Superhawk!

Thank you. Now that I live in SoCal, I kind of wish I still had at least of those bikes today (I lived in Michigan when I was driving them).

Quote (Brian Malone)

It is of the era of motorcycles that used the cylinders and engine cases as structural frame components - who needs a front down tube!

No, the engine was not an integral part of the frame on the Honda CB72/77 series (the CB72 was 247 cc and CB77 was 305 cc). Bikes from companies like Ducati, they were structurally more part of the frame. However, the most notorious of that style of bike was the Vincent Black Shadow, a bike that was very unsafe. It was great as long as the didn't want to stop or turn corners. It had perhaps the worst brakes of any large motorcycle and because there was no real frame, it tended to flex which made it very unstable when turning. That being said, going straight it was one of the fastest motorcycles of it's time. I never drove one and have only seen them in museums, like this one, a 1952 Vincent Black Shadow as seen in the 'Sturgis Motorcycle Museum & Hall of Fame' in Sturgis, South Dakota:


October 2009 (Sony A100)

To give you and idea about how people felt about this overpowered (55 hp) English bike (with English brakes and ignition system), journalist and author Hunter S. Thompson once wrote that "If you rode the Black Shadow at top speed for any length of time, you would almost certainly die. That is why there are not many life members of the Vincent Black Shadow Society." The bike is mentioned several times in Thompson's 1971 novel, 'Fear and Loathing in Las Vegas'.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Brian Malone, engines are stressed members in all modern motorcycle frames to my knowledge. The swingarm pivot is located in the engine case.

On the subject of timing chains, the Euros are bad at applying plastics. The timing chain guides on Euro engines will fail. It seems like they buy plastics by name but forget that polyamide can have a very wide range of properties based on resin within the same plastic name. Otherwise, most other engines manufacturers have timing chain systems that will regularly last the life of the rest of the vehicle.

@TugboatEng (Re: Brian Malone); I read that as being literally integrated into the frame such that the bike would not even be assembled if not for the motor being present ("who needs a front down tube!"). The engine being a "stressed member" seems like a necessity, but if anything due to consequence of the 'packaging' rather than a desire to do so. Of course, now I need to go check my bike to see if indeed the swingarm actually connects to the engine directly-- I'm fairly certain it does not, otherwise similar to the way I interpreted Brian's comment above, you then couldn't remove the engine without effectively disassembling the bike (in this case the rear).

Most bikes don't have the swingarm pivot integrated with the crankcases, but that alone doesn't stop the engine from being part of the structure. It contributes to the stiffness via the engine mounts. It's not unusual nowadays for the front engine mounts in particular, to be designed to be stiff in certain directions but allow compliance in other directions.

Yes; nearly unavoidable, it makes sense to take advantage of it. I thought that's what I was alluding to but :shrug:.

Thanks to all for the info on the use of the engine as a stressed frame member. I have owned only motocross and enduro motorcycles and quite unaware of the constructions used for the large street bikes. 😀

My sister had a 1970 Chevy Vega. It was my job to keep it running. If there are any still left in the world, this engine has problems. I think they were burning oil before you finished the test drive.
https://en.wikipedia.org/wiki/Chevrolet_2300_engin...

Brad Waybright

The more you know, the more you know you don't know.

Quote (thebard3)

...Chevy Vega...

Found this after looking at the wiki page.

My folks gave away their '76 Vega wagon two years ago, great lil car with well over 200k on it. It became a spare vehicle ~1990 and part of me wishes I'd kept it to restore but unfortunately I have too many projects and not enough time.

Surprised nobody mentioned rotax yet.

The Armstrong 500 was a dog.

And the aviation engines keep pilots in practice for forced landings

Or Rotec

https://www.youtube.com/watch?v=LlPtMVijIzs

I had a 76 Vega wagon. OK car, but the door seals leaked rainwater into the car. Nothing I could do fixed it. I had to drill holes in the footwells to let the water out :)

The problem with sloppy work is that the supply FAR EXCEEDS the demand

B&S 1 cylinder intek aircooled, cam compression release system failures, and head gasket failures. Kohler command cracked crank cases.

My sister's aforementioned Vega not only suffered engine problems. Manual transmissions failed twice. Door and hood hinges were constructed of stamped steel with hardened bushings spot-welded on. The spot welds broke and the doors and hood just kind of hung out wherever they felt like. With a forward opening hood, the hood had a tendency to overlap the front cowling and would then get bent straight up if you weren't careful when opening it. It wasn't a problem for me, but because this car broke down so much and all the guys trying to get sway with my sister by trying to help, I could always tell when someone else had been in there. The in-tank fuel pump failed twice. Just a short list of the litany of problems that I can remember.
The whole thing was an engineering disaster. I'd consider the Vega to be the 737-MAX of automobiles, only way worse. Conversely, my brother and later my sister each had a Pinto. They were wonderful cars by comparison.
Brad Waybright

The more you know, the more you know you don't know.

My Vega was fairly reliable, as I recall. Now around here the Pintos pretty much all got turned into dirt track cars.

Pretty sure Vegas mostly got turned into scrap :)

The problem with sloppy work is that the supply FAR EXCEEDS the demand

"B&S 1 cylinder intek aircooled, cam compression release system failures".

Years ago, this cost me many hours of frustration, and the scrapping of a $2,000 riding mower. Now I find this easy fix:

https://www.youtube.com/watch?v=ggV0wS6VMSs

Just momentarily block the air intake while cranking.

enginesrus - I have looked at the youtube videos and various weblinks on the Rotec engine and I am still at a loss to know what/where is the failure mode? The engine design seems quite amazing and compact (for a radial configuration), and it is well suited for its intended use, and the company owner, Paul Chernikeef seems to be engaged in the actual hands-on design, specification, machining and assembly and test of the engines but the horror stories (and near tragic outcomes) presented by many of the videos seem to indicate otherwise. This engine looks beautiful, seems to run well when everything is right. The failures seem to be shoddy materials and assembly rather than an intrinsic fault of the mechanical design. The video you linked points out o-ring/quad ring seal retained with super glue and Paul is quoted as stating they use the glue as standard practice. Is this callous disregard for proper engineering or a lack of understanding of seal retention and the limitations of cyanoacrylates in an environment with fuels, etc.? The video indicates many other mechanical errors such as incorrect lengths on fasteners and shafts. The Rotec looks like an amazing design effort- amazing billet machined components and precision die-castings. Are the engine failures just poor assembly technique? Does Rotec get by with this because the engine is sold as an experimental aircraft engine so it does not have to meet any industry/regulatory certifications?

The Rotec, not seeing one in person and doing a close study of the parts, and just seeing various video's on them, it looks like there are some not very well thought out parts used, and like you say improper materials and heat treat. It sounds like the customer relations isn't too great either.



Compositepro (Chemical)
Yeah and you can turn it a bit by hand too off compression, to give in a running head start. The big problem is when the parts that broke move like if you go over a bump, and broke parts get bounced into the moving parts, not so good things can happen.
Even repairing those engines is no guarantee it will not break again, the system is a good idea but not built correctly, why is that? Sarcastically its not because of engineering!
Then there is the ill designed cylinder head, block deck interface, that can barely hold the head gasket in place, why is that? Yup engineering disaster.

Engineering Disasters, isn't that what this section here on this site is about?

Engineering failures / disasters end up costing someone something.

There really is no excuse for most of these engine problems nowadays. Do they just not test things and depend solely on a computer simulation these days? I just don't see how else this can happen.
Or is it that there are no more real machinists that do the preliminary fabrication and building these engines, that can point out to the engineer that this won't work well or last too long.

Design for manufacturability and Design for reliability are all parts of the design process; world's best design is pointless if you can't make and it won't stay working.

TTFN (ta ta for now)
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Op has very clearly never designed anything for mass production.

I was referring to the Rotec issues called out in the YouTube video. The problems described are essentially manufacturing defects, but for the company, or the tech support, or the designer to ignore or blow off these problems is a sign of a bad corporate culture, and THAT is an engineering failure. The apparent lack of tolerancing and manufacturing tolerance control is an engineering failure. The apparent lack of manufacturing materiel control/requirements is an engineering failure.

TTFN (ta ta for now)
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Quote (SnTMan)

My Vega was fairly reliable

You said 'Vega' and 'reliable in the same sentence.

Brad Waybright

The more you know, the more you know you don't know.

LOL, yeah, I get it, but it was. Fairly...

The problem with sloppy work is that the supply FAR EXCEEDS the demand

I mean... as long as all four wheels were on holding up the rest of the car and the roof is intact, it is 'fairly' reliable as a rolling storage shed.

Quote:

Op has very clearly never designed anything for mass production.

It should be "never designed anything for Lowes and Home Depot consumer level mass production".

You could build almost any consumer item to last, but hardly anyone would buy it because it cost more than the penny pinched one on the shelf beside it.

Also, calling the quality of a low end consumer grade Home Depot engine an engineering disaster is a big stretch. If it doesn't have the potential to kill then it's hardly a disaster.

Engineering disaster doesn't always have to be associated with life loss, it can be something that costs someone something. Money, life, their mind, body parts etc. etc.
Again there is just no excuse for the, for lack of better terms, the stupidity of some of the designs, especially when there is an existing design that has been proven, for in some cases almost a century.
It just makes no sense when simple "just look at it" logic is thrown out the door, for example that cylinder head deck interface.

Mass production? yeah the items I worked on where always very expensive, not the normal box store stuff.

'worked on'(whatever that means) != designed and walked through tens of thousands of test hours the products about which you constantly complain go through between concept inception and release for sale.

I could clarify my statement and just say its clear to me you've not ever designed anything using an engineering process, whether mass produced or not. You have literally no idea what's involved, and no idea why the things you complain about on this forum are the way they are.

Credit where credit is due though- calling a system failure on a lawnmower engine an ENGINEERING DISASTER is hilarious. So I guess that's a mark in the plus column.

The sign of a real professional is one that does not belittle someone else.

Now lets get back to Engine designs. So how come there are some manufactures that have such a difficult time getting roller lifters to last? What is causing this? I know of many engines in the past that used the same that had very long lives.

You find a new forum complaint thread somewhere?

@enginesrus I'm not belittling you. I'm not criticizing you personally. I don't know you.

I AM criticizing your approach to whatever it is you're trying to accomplish by posting here.

I'm sure there are aspects of your life in which you're an expert. The area of evaluating the work of engineers is not one of them. There is no shame in that. I'm not an expert in recruiting college athletes. There's no shame in that, but I also don't go to college recruiting forums full of college coaches and tell them all how they're doing it all wrong and how Bear Bryant had it right in 1975 and all that's happened since then is devolution.

You constantly post complaints about all manner of things which seem to be rarely, if ever, based in empirical fact. When you're presented with information contrary to your non-fact-based opinions, you bristle and ignore it.

That's fundamentally not what engineers do, and it's contrary to the value and culture of this forum. You could change that by not dying on the hill of your own opinion, and actually taking the time to read and internalize rebuttals to the things you post. The trend so far seems to indicate that you won't ever do that, but ultimately the only person on this forum who can save your reputation is you.

Quote (enginesrus)

...some manufactures that have such a difficult time getting roller lifters to last? What is causing this?

Claiming no expertise, my guess is the cylinder de-activation schemes that have (relatively) recently come in to play. My only experience is with the FCA 5.7.

Not all engines that have roller-cam-follower issues have cylinder de-activation. The Pentastar V6 is another one, and it does not have cylinder de-activation.

I have one of those. A new rocker is a $20-ish part. It's a few hours labour to replace if one goes bad. Meh.

(N.B. It's way more labour-intensive to replace a failed roller lifter on a pushrod Hemi. The Pentastar is DOHC, and you can get enough clearance to replace those lifters without fully removing the camshafts - just loosen the camshaft caps enough to get sufficient clearance to get them out and in.)

BrianPetersen (Mechanical)
---------------
What usually fails on them? Needle bearings? The roller ? The pin? Have they determined if it is a material issue, or a quality of lubricant issue?





LionelHutz (Electrical)
13 May 22 11:45
You find a new forum complaint thread somewhere?
--------------------
This particular area is about Engineering Disasters, meaning some huge failures caused by bad engineering, so this is the correct place.

All of these engines get torture tested before going in to production but the testing is done with the manufacturer supplied oil. The manufacturer has no control once the product is in the hands of the consumer. For all we know, these failures are caused by consumers running the Shell Rotella oil because it's the best. 🙄

Some of the failures are on low mile engines, for warranty reasons, not many folks want to mess up with factory recommended oil changes.

Something that marine engines do that auto engines don't, they run all the time.

The first thing an automotive engine design has to do before it gets any real development is to run for 100 hours continuous at peak power. If it survives that (some engines (eg Austin A+ turbo) do first time, others take months to get to that point (redacted), and others never get there (many SI to CI conversions in the 80s)) then it is deemed worthy of further development.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

Talk about problems. All this to get to the radiator drain.



🥵

GregLocock (Automotive)
14 May 22 09:40
The first thing an automotive engine design has to do before it gets any real development is to run for 100 hours continuous at peak power. If it survives that (some engines (eg Austin A+ turbo) do first time, others take months to get to that point (redacted), and others never get there (many SI to CI conversions in the 80s)) then it is deemed worthy of further development.
------------------------------------------

I suppose that is also why the conservative HP ratings on some automotive engines. I wonder if the high HP engines like the Hell Cat Hemi had to do that? Or do they "adjust" to a lower HP for the test?

The drive-by-wire and fully electronically controlled nature of modern super-high-power-output engines allows for the possibility of automatic de-rating based upon whatever sensor readings and mathematical models the calibration department deems appropriate.

Disclaimer, I don't know Chrysler ECU calibration, but it's pretty likely that it'll make that power level for as long as you can keep engine oil temp, trans temp, and coolant temp within range, and as long as internal mathematical models for certain critical component temperatures are satisfied. I do not know if the stock radiator and oil coolers are sufficient for continuous output at that rating ... I tend to suspect not.

Bear in mind that at 707 hp, those cars will drain their entire petrol tank of fuel in about 15 or 20 minutes, so there's an automatic time limit on how long one can sustain that ... and that's assuming Mr Policeman does not have a thing to say about it.

In the motorcycle world, the little 125cc scoots have quite a bit less specific power output than the 1000cc superbikes. It is presumed that the 125cc bikes (which usually have 12 or so horsepower) will be ridden flat out all the time except when a stop sign or traffic signal dictates otherwise, or perhaps in school zones. (Mine is ...) whereas it is presumed that the 1000cc superbikes cannot be ridden at max power output for significant lengths of time, even in track-day service.

My two-cylinder 321cc Yamaha R3 has key cylinder and valve dimensions that are within a millimetre or two of those of a four-cylinder Yamaha R6, but the rev limit is some 3000 rpm lower, and the specific power output is quite a bit lower (it makes about 40% of the power despite having 54% of the displacement). If "all else were equal" this is a bit more than half of an R6 engine ... but it's de-tuned in the interest of driveability and longevity.

On a serious engine dyno you have unlimited cooling (including cooled oil), and also as much ventilation as you need, including spot cooling with eductors. As such running full power tests is not especially traumatic. Having said that fires are perhaps an annual event.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

Hellcats have interesting torque management during transmission shifting, cutting most of the power during the shift.

Yeah, they took away half the fun

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

The sweeping up of transmission bits fun?

Hey, perhaps snapped half shafts too?

At least on early cars, the differential has a nasty habit of ripping itself loose of the chassis before the halfshafts break.

Back in the old days of bear skins and stone knives, (almost) everything was so over designed that it could take it.
Now they have optimized the weight and cost savings of the drivetrain components, just to consume all these weight and cost savings with hardware that has nothing to do with propelling a vehicle from A to B.

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

Lou Scannon, You hit the nail on the head, and how true.

Quote (Lou)

Back in the old days of bear skins and stone knives, (almost) everything was so over designed that it could take it.
Now they have optimized the weight and cost savings of the drivetrain components, just to consume all these weight and cost savings with hardware that has nothing to do with propelling a vehicle from A to B.

They consume it with unnecessarily high performance capabilities as well. Your average grocery getter family sedan has 0-60 times that rivals that of the muscles cars of the 70’s. Why? I guess because that’s what the markets want. That’s what the commercials tell us anyway.

What kind of reliability (and, dare I say, efficiency) could we get out of an engine/vehicle that had a top speed of <80 MPH and a 0-60 time that wasn’t suited 1/4 mile comparisons?

It seems that economy, low emissions, and power go hand in hand. If you have one you can have the others.

I see no reason for the average vehicle to have to weigh in at close to 2 tons. The old VW beetles, and GEO Metro's tip the scales under 1 ton, given that, there is no reason to have more than 140 HP.
The old 235 Chevrolet inline 6 was rated at 140 HP, and could move a fairly heavy car or truck just fine. Absolutely no reason for 700 HP in any normal road car especially where high speeds are not allowed.
High HP? There are very few class 8 heavy trucks that have 700 HP, and for one to come close to a GEO Metro one of those trucks would need close to 2500 HP. MPG ? All this battle to get to high miles per gallon?
GEO Metro has been getting over 40 MPG for the last 33 years or so.

If you want to prioritize efficiency then buy an economy car. The OEs all make them, baby Ecoboosts, Ecotecs, etc are ~100 hp and the cars sell for under $15k brand new. Personally I'm like most and prefer a bit more power and am happy to settle for less economy if I must, but that's not a direct correlation without maintaining the same gearing. In the commercial truck industry for example there are many examples of higher-horsepower trucks having taller gears and getting better fuel economy than the same model with a smaller engine.

Comparing HD diesel power curves to light-duty gas tho is apples and oranges. A 15L making 700 hp is doing so for half the RPM range and will be producing ~2k lb-ft of torque at high idle. The aforementioned Hellcat's making 300 lb-ft at high idle and only producing 700 hp at its peak.

Part of the weight increase is due to better crash structures, part of it is from people not wanting the car to sound and feel like a tin can when opening or closing the doors or when driving over bumps, part of it is from every vehicle generation having to be bigger than the last one so that the marketing people can advertise "more trunk space", "more legroom", etc ... "less trunk space" is not a good marketing plan. Hence, a Honda Fit nowadays is bigger than the second-generation Civic was, and the Civic today dwarfs Honda's original (1970s) "big car" Accord.

Couple vehicles ago, my 2006 VW Jetta, VW's compact car in that era, was very close to the same size as what it replaced, a 1996 Passat - VW's big car of its era.

The modern Fiat 500 that is my daily-driver today is roughly the same size as the first-generation Honda Civic that I learned to drive in, but it weighs almost 50% more. I'd sure take the odds of surviving a crash in the modern car versus the old one ... the crash structures are enormously stronger and it has much better safety equipment, 30 years of development will do that.

Powertrains? The engine sizes are almost the same, 1.4 in the Fiat, 1.5 in the Civic. The newer engine makes more power, although given the weight difference in the vehicle, acceleration is probably about the same. Fuel consumption is also about the same. The Fiat weighs more but the aerodynamics are better. The factor that is orders of magnitude different, are the CO, HC, and NOx emissions.

Durability? The Honda started burning oil after about 120,000 km, and it went to the junkyard with 12 years and about 180,000 km on it, completely rusted out and with nothing good left on it whatsoever. I put on more annual mileage now; the Fiat still runs practically like new with almost 230,000 km on it and the paint and interior are in great shape as well.

"I see no reason for the average vehicle to have to weigh in at close to 2 tons'

Guess what. The only people who car manufacturers listen to are the ones who buy new cars, and the legislators.

30 years ago we made a car with 6 seats, weighed 1418 kg, got around 20 mpgUS, had a 160 hp engine and a manual 5 speed. It had an AM/FM radio with a cassette player and 2 speakers

When we introduced the final model in 2014 it weighed 1704 kg, had only 5 seats (crash) airbags(crash) auto only (customer preference) full climate control (customer preference) dual cats (legislation), got 24 mpgUS, IRS, much bigger (heavier) wheels and tires, ABS, TC, ESC, full audio with 9 speakers including a subwoofer, electric windows, electric seats, met stiffer emissions and crash regs, 261 hp engine (actually the same one). It was faster, quieter, rode better and is more durable.

Now we didn't put that stuff in for fun, we did it because the people who buy new cars wanted that stuff and were prepared to pay for it.

Cheers

Greg Locock


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Back on topic.
BMW engines and their bearing failure problems, and timing chain guides and oil pump drive chain failures.
How many Engines can we list with these sort of problems?

The Porsche engine recall about a year ago? Possible cracked connecting rods? I would like to know what they are made from? Are they PM?

Quote (enginesrus)

Back on topic.
BMW engines and their bearing failure problems, and timing chain guides and oil pump drive chain failures.
How many Engines can we list with these sort of problems?

We were on topic, but I digress.

Where's the data?

Quote (enginesrus)

The Porsche engine recall about a year ago? Possible cracked connecting rods? I would like to know what they are made from? Are they PM?

Ooo. For this one, we actually have data. This one affected me directly - I know the situation well. The recall was issued after an issue was found with a particular batch of rods during QC testing at the plant in Zuffenhausen.

Total 718 production for 2021 was 21,250.

Total number of vehicles affected by the connecting rod recall was 190. That's 0.8% for those of you playing along at home.

Of the 190 vehicles affected, only 20 had actually been delivered at the time the recall was issued. That's 0.09%.

Where's the disaster?

But what if a Porsche 718 was those 20 people's only means of transportation?

They will just have to Zoom during the Board of Directors meeting.

Somebody needs to save a few of these posts as an example of how to either get yourself uninvited from DFMEA reviews or into trouble.

Me: Possible effects? Customer dissatisfaction.

Theywhodontwanttobethere: The engine could brick itself causing a reduction in braking force, a loss of control, and a pregnant nun's vehicle going off a bridge, landing on a schoolbus full of kids, and....

If they wanted to "Zoom" they should have bought a Mazda.

Quote (CWB1)

Me: Possible effects? Customer dissatisfaction.

So you're saying the Aztec didn't have a row in the DFMEA that included customer perception?

Quote (TugboatEng)

If they wanted to "Zoom" they should have bought a Mazda.

...I've had three; still have one and it's coming up on 25 years old (I've had it for ~16).

Quote (Spartan5)

...Your average grocery getter family sedan has 0-60 times that rivals that of the muscles cars of the 70’s. Why?...

Because it makes my wife happy. She wanted a Charger and we bought a 3.6 powered model, it later needed minor repair and the loaner was a 5.7 - the moment she started it up I knew it would end up hers. And if she asks for a 6.4 or a Hellcat, she will get it.

So what material are or were the connecting rods made from? Its just not normal for new connecting rods to have that sort of problem. And yes if the engine would have locked up on a congested freeway at the speed limit it could be a potential disaster. What other engine makes in road vehicles have had flawed connecting rods in the past? I can't think of any, bearing problems yes.
I read that Porsche was using PM to make crankshafts, is that true? If so then the rods must be sintered as well, and would fully explain the problem.

GM has been using sintered rods for nearly 3 decades. That is not a root cause of the Porsche problem.

Quote (enginesrus)

Its just not normal for new connecting rods to have that sort of problem. And yes if the engine would have locked up on a congested freeway at the speed limit it could be a potential disaster.

This subforum is 'engineering failures and disasters', not 'things which happened which had a small probability of resulting in property damage if they hadn't been caught during QC processes and properly addressed by the manufacturer before reaching the market in significant quantities'

Quote:

Its just not normal for new connecting rods to have that sort of problem.

Everything has "that" problem, its called quality issues. We're manufacturing far more parts with far more complexity, with far fewer people, and doing so at a rate far faster than ever before. Even with ever-evolving QAQC crap happens and bad parts slip through accidentally. Occasionally vehicles are built with "bad" parts bc delaying sales is more costly than a warranty repair for minor issues. If issues didn't arise then OSHA and insurance companies wouldn't require hard hats and steel toes on plant floors. On the brighter side, for most every issue there's a severely underappreciated miracle of modern manufacturing.

I'm also still waiting to read about any actual disasters in this thread.

A few bad connecting rods is the best you can produce? Big deal.

I'll tell you a manufacturing one. Started to get field reports of crank position sensors being destroyed on high mileage cars. The CPS reads a tonewheel on the engine side of the front pulley.

Problem engines bought in, noticed that the cranks were slopping forwards and backwards, hence ramming the pulley into the CPS.

Looked at the thrust washer, and the crank was worn away, allowing the motion.

By this time practically the whole engine section was involved to some extent, obviously with the engine lab taking the lead.

So they did an Is/Is not, and identified the time period when the problem started.

Back over to the factory, found that the lapping machine had been refurbished at that date. For some reason they had reversed the direction it lapped in, and the new direction increased the wear rate.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

I have owned three vehicle with gear driven cams:

1987 Honda CB1 motorcycle
1998 Honda VFR800 motorcycle
1987 Subaru BRAT

Then there was the major problems with sludge formation, in many different brands of automobile engines.

From the 1950's into the 70's, there were not many engine design failures, they were battling cam and tappet wear, and sludging in the 50's. Leaded fuel was not a huge help for engine durability in those days.
The choice from large recip aircraft engine manufactures, to use flammable magnesium castings for nose, accessory, and diffuser cases was a disaster waiting to happen, and many lives were lost because of it.

echo...echo...echo...

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

50s engines weren't designed to last more than 50,000 miles with frequent oil changes and lots of screwing around with breaker points and distributor caps and that's not an engineering failure, and the modern engine that runs like new at almost 150,000 miles is a failure because it's hard to get the alternator out even though it hasn't needed service??

Quote (enginesrus)

and many lives were lost because of it.

how many, exactly?

Quote:

The choice from large recip aircraft engine manufactures, to use flammable magnesium castings for nose, accessory, and diffuser cases was a disaster waiting to happen, and many lives were lost because of it.

Titanium is considered a flammable metal as well. Lots of titanium components in modern jet engines.

Well... so is flour.

Actually, flour is explosive, as is starch.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Titanium is not THAT flammable; it was still being specified for armor-protection 15 years ago.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

If you get it hot enough, even iron burns.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Titanium powder...

Quote (TugboatEng)

Titanium is considered a flammable metal as well. Lots of titanium components in modern jet engines.

It so happens that I'm on holidays this week, currently surfing the net while sitting on a patio after a day of riding my 2004 Kawasaki motorcycle which right now has just short of 123,000 km on it. It's sitting right in front of me as I write this.

It has titanium exhaust headers! (Very light.) edit: And a magnesium valve cover, and a magnesium clutch cover.

And yet ... it's not on fire! And it has managed 123,000 km of not catching fire so far. Maybe it blows up tomorrow. If it does, I've had my money's worth!

Almost anything burns if the surface area is high enough (e.g. a powder), it's in contact with an oxidizer (e.g. oxygen), and there's enough energy input to allow a reaction (e.g. heat). Chlorine Trifluoride is a strong enough oxidizer to burn sand. The only things that aren't flammable at some point are the strong oxidizers themselves, they're on the wrong side of the reaction to count. And even then, if you've got a stronger oxidizer you can burn a lesser, e.g. Fluorine can "burn" oxygen as a fuel.

Quote:

Almost anything burns if the surface area is high enough (e.g. a powder), it's in contact with an oxidizer (e.g. oxygen), and there's enough energy input to allow a reaction (e.g. heat).

Sure, but the discussion was about the environment around an engine; titanium, even when under ballistic impacts, is not flammable, so engine compartments and exhaust are unlikely to cause titanium-induced fires.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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Quote (Leaded fuel was not a huge help for engine durability in those days.)

I understood it was a big help... reducing pre-detonation from 'lighter' hydrocarbons in the gasoline mix...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik

Quote (modern engine that runs like new at almost 150,000 miles is a failure because it's hard to get the alternator out even though it hasn't needed service??)

I think it was my 68 Chevelle... have you ever tried to replace the starter motor?

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik

It's the "heavy" hydrocarbons that cause pre-detonation in gasoline engines. Diesel fuel, for example, has quite a low octane of around 30. Lubricating oils are worse. Engines with high oil consumption are more prone to pre-detonation.

Surprised nobody has mentioned mazdas Wankel engine yet.

Everyone I know that has owned one has only done it once and were on first name terms with pretty much everyone at the garage.

I have found most of the OP's failures to be opinions and not strongly supported failures of engineering. But that is my opinion . . .

I am glad I did look at this thread because I was made aware of these fine and very detailed references.

Amazing history of engineering - everything I thought was amazing engineering in F1 racing engines came from or developed from pre-WW2 and WW2:

Quote (drawoh)

An excellent book on engine development during WWII is The Secret Horsepower Race by Calum Douglas

This is an excellent book.

Fascinating backstory on the Vega engine development:

Quote (BiPolarMoment)

https://www.hemmings.com/stories/2020/06/23/ask-a-...

I hope to find a book on the Vega engine development.

Often, many engineering advancements are built on the data and analysis collected prior.

Can't wait for the sequel "Maintenance disasters", I'm sure we all harbour a few opinions about that.

Or maybe "Lack of Maintenance Disasters".

Or Shade Tree maintenance disasters. My favorite example is chassis lubrication. Modern vehicles have long lasting seals made from EPDM rubber that is subject to damage from all greases that are available at the auto parts store. People complain about the removal of the zerk fitting but don't realize that they're actually doing damage by lubricating. The worst part is, if you try to explain this or document it the shade trees just root deeper.

For what its worth

I bought a Honda Fit to replace my old sports cars/off roaders i drove when younger. Was sick of spending time and money on cars. Wanted something boring that wouldn't give me grief.

3 years later at 125,000km I need to replace the engine. cylinder ring is gone on the third cylinder.

cheaper to get a new engine than to fix. cars these days are getting to be a bit like home appliances... just throw away and replace.

You bought a car that was designed to be cheap and in the world of nearly $200 an hour labor any repair must be fast or you'll exceed the cost of the car. Thankfully Honda had complete engines available so you didn't have to waste all of that money on labor.

But the real problem is the cost of labor and the auto manufacturers have nothing to do with that. I have a block I need decked for a new head gasket and there is a months long lead time to get it under the mill.

In context a new short engine costs a car company about $2000, it would be easy to spend that on tearing an engine down, regrinding the bore, and replacing the piston and ring. The days of the UKP 25 cylinder head rebuild are long dead.

Cheers

Greg Locock


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Hagerty Media: "Bronco engine investigated for “catastrophic” failure".

Stay tuned, I guess :)

The problem with sloppy work is that the supply FAR EXCEEDS the demand

This is relatively old news to those of us with orders placed.

It's been traced to a bad batch of valves which have been suffering stem failures. There's more failures so far than they are reporting there - last I was on the forum a couple of days ago, I believe the failure count was in the low 50s.

The 2.7 EcoBoost in the Bronco is the same one that's in the F150, isn't it? If not, what's different? If it is, doesn't the issue also affect F150?

I believe the are substantially the same. There are some accessory plumbing differences (Bronco engine bay is significantly smaller). Both engines are produced at the Lima engine plant - but I believe they are different enough to run on different lines, which would explain a batch of flawed valves making it onto one platform and not the other.

Problems with valve stems? Gosh even in the war days with very poor grade of materials Germany could make decent valve stems. So the question is who is the real valve manufacture of these costly broken valves?
All of this having parts sub contracted from out of country, ends up costing us. Manufacturing needs to be 100% in house, so tight controls are kept on processes. Huge engineering failure.

How exactly do you know that German valves made during WWII were 'decent'?

And what exactly makes a 'decent' valve?

Who is the 'us' you think this particular failure is costing? Do you own a Bronco or have one on order?

Do you know who supplies the valves in question?

Do you know where they are manufactured?

Do you actually know anything about this problem, or are you just happy to claim the sky is falling?

Speaking of timing chains, how about the one on the Ford 427 SOHC. I read somewhere it is around 6 feet long.

You have a criticism of that design, considering its purpose?

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

Hi Lou,

I don't have any criticism of the design. It's amazing for a relatively short term development in the 60's. Timing chains came up and I thought the Cammer was interesting because of the length of the timing chain and its arrangement. The main problem with it was the NASCAR banned it in the fashion it banned the Boss 429.

Kyle

The Cammer was never sold in a production passenger car, so it did not qualify for Nascar homologation.
The Boss 429 was allowed to qualify for Nascar homologation, I assume by negotiations between Ford and Nascar, with the intent of providing worthy competition to Chrysler's mighty Hemi, which had been dominating the high speed tracks since 1966. (There's a lot more to the story, which you probably know, so I will leave it at that, so as not to hijack this thread more than necessary.)

"Schiefgehen wird, was schiefgehen kann" - das Murphygesetz

Mazda rotaries - we had an RX3, a 1973 or '74?
Ran great, not super powerful but pretty peppy. Wouldn't quite do 80 mph over the top of Cajon Pass.
(picked up one of my brothers at LAX, accidentally drove most of the way home in 2nd gear before I noticed. Yes we were on the freeway)
At 80k miles its o-rings failed, allowing coolant into the chambers.
The family kind of sat and procrastinated, eventually I took its motor and another one wit the same problem apart.
It had sat around rusting for a while, so I had a devil of a time getting enough of the apex seals out intact.
But By mixing and matching, I got that sucker back together (new face seals and o-rings, refaced end and middle cases) and it ran fine.\
It ran for many years after that, until if got crashed again (sister got rear ended, I think) and she retired it in favor of a Torino.
(yeah, that must have been a shock to the driving perceptions)
So I consider the rotary to be a very decent motor.

Jay Maechtlen
http://www.laserpubs.com/techcomm

The RX up to 7 were fine because they were competing against a lot of lazy development. The RX8 proved the rotary engine is a novelty in today's world.

This section is called "Engineering Failures and Disasters" I've posted mostly Engineering Failures. And an engineering failure as related to Engines is the failure of the engineering department to properly design said engine or parts. In some cases rather than improve a bad design it is made similar but worse. Can anyone think of any examples? The "Disaster" part is when many people are financially stuck with the results of the bad design, or life is lost because of it.
And all joking aside, some cases of magnesium fires in the piston airliners during rain events was catastrophic, there is information out there about it.

not car engines but saw a 2 stroke opposing piston diesel engine self destruct which thankfully never killed anyone but a couple were in hospital for a while.

It was a tank engine and one of the fuel pipes fractured when the power pack was being replaced.

This was on the return line.

So it ran fine but filled up the engine bay.

When the engine turned off it started sucking fuel back through the return line and self feeding the engine. The revs went through the roof and quite quickly engine block failed above 10000 rpm. The gun barrel was over the engine bay for test driving and it blew the turret off and sprayed hot metal upwards and ignited the fuel left in the engine bay.

One broken leg off the turret and 1 nasty life altering burn resulted.

The fix was to put a nonreturn valve hard after the metering setup. Previously it was the other side of the fuel decouple in the engine bay. To change a power pack you had to decouple I think it was 2 fuel lines, 4 hydraulic and 3 electrical connections you could do it and swap the pack in under 30 mins.

Never cared or the pressure-timed injection on the old Cummins engines. Unit injectors in the head, injection quantity was directly proportional to supply pressure, normally controlled by the governor. I think you can imagine what happens when a return line valve is closed and places back pressure on the system.

What gets me is when a problem exists with a certain brand engine in X series, and is known to happen for some years, no improvements are made or even attempted. Why?
What usually happens is the company's reputation starts to slowly go down the sewer.

Money...

"Known problems" are usually grossly overrated. Several of the issues mentioned above are great examples - "known problems" that only affect a tiny percentage of total production or cost relatively little to fix, and are only really 'known problems" bc ignorant old men need something to gripe about besides the weather and youth.

"Reputation" is worse in that its often contrary to fact. Many studies of dual-branded vehicles have shown vastly different opinions of vehicles differing only in the badges. Its unfortunate, but preconceived notions and popular advertising shape reputations more than quality, and the general public largely cannot differentiate between paid advertising and hobbyist/entertainment rags/sites/awards.

The fact that people buy BMW and VAG vehicles is proof that they don't care about "known problem".

I had two VW diesels that I took past 400,000 km, and the first one was in a model range with a big black mark in the Consumer Reports ratings.

Some of that big black mark was due to 1990s-era VW automatic transmissions. Mine was manual.

Some of that big black mark was due to sunroof drains becoming blocked and causing water to get into places that it shouldn't be. Mine didn't have a sunroof.

Some of that big black mark was due to various issues with the early VW VR6 petrol engines, which this model was a recipient of. Mine had the 1.9 litre 4 cylinder diesel engine, and it was bulletproof. And changing the timing belt was a reasonable do-it-yourself job, which I did myself a few times.

Some of that big black mark was due to certain electrical and electronic issues, and I will grant that the power supply for the instrument cluster was a weak point. Someone didn't do their cold-weather weak-battery validation well enough.

I sold that car with 462,000 km on it. Original clutch (although it was due), original transmission, original engine still running well, everything still worked. It needed to be taken off the road for a month to sort out various suspension-and-steering issues, and the paint needed attention to delay the onset of rust (it still looked good but you could tell that it needed attention), and as far as I know, the VW spare-time-mechanic who bought it from me, did just that and kept on driving. I saw it in a parking lot in a town near where I sold it some years later, and it still looked good.

It may have had the feared big black mark in Consumer Reports ... but my example was a good car.

So then if said engine has constant head gasket failures that is no big deal, and should not be redesigned to prevent it?

That depends on the cause of the head gasket failures. I wouldn't redesign an entire engine due to a faulty radiator or head gasket design.

Today it seems that the standard for engine durability is for most of them to make it past the warranty period, then if the head gasket lets, engine throws a rod, or whatever-
sorry, it is out of warranty. Looks to me like FCA/Stellantis addressed their issues with the Hemi by changing the warranty from 5 year/100K miles to 5 year/60K miles. Replacing wiped out
camshafts costs money.

What was the warranty period on a Chrysler 440?

Quote (wayne440)

Today it seems that the standard for engine durability is for most of them to make it past the warranty period

The standard for engine durability for as long as warranties have existed has been for most of them to make it past the warranty period.

Warranty periods today are longer across the board - and in a lot of cases MUCH longer and more comprehensive - than the warranties from the era OP worships.

Todays engines are better in literally every respect... these arguments are straight up ridiculous.

In 1965 Chrysler was actually the first to offer 5 yr/50,000 mile powertrain warranties. This applied to every model sold from 1965 through 1972, except anything with a Hemi or 440 six pack; those models had 1 year and 12,000 miles, voided if the car was used in competition of any sort (ha ha).

In 1972 they changed the warranty for all models to.... 1 year and 12,000 miles. Why? Because the products they sold between 1965 and 1972 had not been all that reliable in the aggregate, and they lost MILLIONS of dollars on warranty coverage. Millions. Total Chrysler sales from '65 to '72 were over a million cars, and the average warranty cost per vehicle around that time was around $40. That's $40,000,000 in 1970 dollars.. that's an astronomical amount of money.

Sorry gents, but these fever dreams about bulletproof muscle cars from the 60s are total bull.

The cause for the failure is no bolts (fasteners) in the area to hold enough pressure on the gasket. Well that seems to be a common theme these days. This engine has other problems as well.

Are you blathering about Focus RS head gaskets again?

Subaru's notorious head gasket failures had nothing to do with insufficient clamping force.

Quote:

In 1965 Chrysler was actually the first to offer 5 yr/50,000 mile powertrain warranties. This applied to every model sold from 1965 through 1972, except anything with a Hemi or 440 six pack; those models had 1 year and 12,000 miles, voided if the car was used in competition of any sort (ha ha).

And today the factories all warranty track failures under the regular 3/36 or better warranty. They'll even finance you a rollbar and time at their driving school as part of the vehicle purchase.

Still more blathering, still no data.

Quote:

And today the factories all warranty track failures under the regular 3/36 or better warranty. They'll even finance you a rollbar and time at their driving school as part of the vehicle purchase.

And on top of that, the fire-breathing halo models are covered by that warranty too.

Yup. Given the high cost and low-volume I can understand warrantying those, the shocker for me is that they do the same with high-volume base cars.

Small OHV engine is the topic in above post. Data? How can an entity that is not the manufacture or main lead of the dealer network acquire data? The data offerings are the many websites and video's that show the continuous problems. And like any other consumer item that can at times just end up in a scrap heap, the true data that a manufacture has, probably doesn't even come close to the real number.
You know like home testing for covid, how many positives are not reported? Data in many cases is not relevant. When the engine is out of warranty, how can data be obtained? With all the aftermarket parts available it can not be done through parts sales. So the only data available is hitting the web, and seeing the common failure points and how those failures keep repeating on the same engine. When you constantly ask for data what do you want? Would you want to see page after page of website links? I don't think this site would want tons of that posted here. Nor would most anyone here even look at them.
If one was truly interested in data on this particular topic, just travel the country and visit shops that deal with the products. I know this (constant asking for data) is not a case of really desiring data, it is just an arguing point.
All this goofy abstract data hunting is the problem with engineering now. Just look at the problem and come up with a fix. This is the main reason all us consumers are stuck with costly junk that will not last, past a warranty period.
MCAS comes to mind, why fix it whats the data? Only 2 planes out of how many? Very low percentage why bother. That is what I see here when I post about these various problems.

I think there was 400 ish delivered when it was grounded.


But they track the accident rate by hours flown or number of flights.

And Boeing didn't want to fix it. And at this rate the max 10 is not going to be certified before the certification standards change.

I used that as an example. The engines I'm talking about have a huge failure rate, and essentially no effort made to improve the design. But then it helps sell parts, service, and new engines. Biggest problem is it can put company out of business, and it sort of did. After seeing how things are going nowadays, maybe that was the plan.

Quote (enginesrus)

When you constantly ask for data what do you want?

We (specifically, I) have been extremely clear across many of your threads about what data we would want in order to take your myriad complaints seriously, and have a real discussion about whether something is a problem, or not:

RATE.

Failure RATE is by far the most important data point. And it isn't just a point of argument. If you started one of these threads and said specifically 'Engine X has a failure rate of 8% on component B' after XXX number of average hours or miles, is this an engineering failure??' the responses you would get would be categorically different.

But you don't do that, because you have NO idea what failure rates are on the stuff you complain about. Example:

Quote (enginesrus)

The engines I'm talking about have a huge failure rate

Ohhhhh really? What engines, specifically, and what is the actual failure rate? If you actually have these numbers I'll be shocked, but we'd have something to talk about.

Quote (enginesrus)

MCAS comes to mind, why fix it whats the data?

If you don't know the difference between a design problem that kills 350 people and a design 'problem' that costs the owner of a 15 year old truck $2,000 9 years and 150,000 miles after the warranty expired... I guess. Wow. We cleared the shark by an even higher margin than I thought.

While this article is not directly related to engine issues, it's still an interesting read:

Car Brands With the Most Problems

https://www.thestreet.com/personal-finance/car-bra...

Note that with my new (June 2021) GMC Terrain, the only real problem that I've had is with the on-board navigation system (just like it was noted in the item above as being where most of the issues are appearing). It has stopped working a least a half-dozen times over the past year but of course, when I take it to the dealer, it's always working. They've replaced the data chip that has the maps, but it's not specifically the navigator that's shutting down, it's everything thing that connects to the panel where the chip is inserted, including the auxiliary audio connection (for my iPod), the iPhone connection for Apple CarPlay as well as the Bluetooth iPhone connection. When it's acting up, none of these things work. The radio works and no other electronics seem to be effected, but every associated with the navigator and connecting external devices, they stop working. In the first couple of months, it was happening quite often, however its been at least four or five months now since the last incident so maybe the last time the dealer had it, they did move something or tighten something that fixed the problem.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Severity and frequency are two separate metrics. Failures with a high frequency usually just mean high warranty costs, failures with high severity often mean recalls, lawsuits, and possibly jail time. Harming the public is never statistically acceptable, repairs OTOH are expected. Reading the internet or asking a mechanic is a good way to identify common issues with any vehicle or product. The problem is that it tends to grossly misconstrue the frequency of their occurrence.

OEMs do closely guard their data streams and warranty databases to avoid misuse but don't doubt its accuracy for modern vehicles and equipment. Most vehicles stateside were self-reporting failures by the mid-Y2ks, and many were even actively reporting location and live data otherwise. They've built various profitable services around it like updating 3rd party GPS maps, theft/repo recovery, rental monitoring, predictive maintenance (swap parts before failure to avoid downtime), etc, and engineers find all manner of development uses.

You think car engines are bad...

You should see the aero engine issues.

We have been waiting 3 years now for P&W to redesign the engine bleed duct system to get rid of the acoustic harmonic which was causing disck failures.

Alistair Heaton, I'm not just pointing out car engines failures. All IC engines here, not a huge turbine person though, but I would like to hear more about the P&W, tell us more about it.
I remember not too long ago one of the recip aircraft engine manufactures had a huge problem with failed lifters, from out of house manufacturing outfits. I have searched for that article and is now nowhere to be found. Personally I have never been impressed with those small aircraft engines, especially the construction methods.

There is an issue with the low pressure compressor and its failure.

It's to do with the swap over between the high pressure bleed and low pressure. There are operational procedure changes to protect against it.

I am positioning today and just on the phone. When I get near a computer I will do the subject more justic from a pilots point of view. There will be others in the forum who can do the engineering of the problem more justice.

Right in about 2019 there was 3 inflight engine failures on the A220

The lp compressor rotor was found to be the common failure point due cracking.

The FAA required frequent boroscope inspections after an initial grounding inspection.

It started just after a FADEC software update in 2019.

Crews had to manually limit the max N1 during climb from memory to 93% by taking the Auto throttle out. You could reengage it during the cruise but most of us didn't because if you hit some sink the AT would then power up to over 93% and then the engines would require an inspection which took 36 hours because it had to be left to cool otherwise you would melt the borescope and then the inspection done and paper work. So we just left it out and set a N1% and left it there.

There is something going on with the bleed duct system. If you have ever heard one after start it makes a howling noise after the APU is turned off and the engines take over the bleed power. While there is no load it uses the lp port off the LP compressor and when load comes on at low power settings it needs the HP port. As it swaps valves there is a resonance generated. It does this in flight as well when you power up configuring to land. It is extremely distinctive. IN fact some pilots use it to let the family know they will be home in the next 40 mins. They power up and down a couple of times, while flying near their houses.

Medium term solution was to up date the FADEC software with the new limitations which reduces the climb thrust and now we can keep the AT in.

Long term is they are going to mod the bleed system and then update the FADEC again after that.

There is something else going on with the rear turbine seals at the moment and deltaP over them at high altitude and low thrust settings leading to the premature failure and high oil consumption. We deal with that by starting a slow decent early so it keeps some power on until we get to lower levels and higher static pressure.

Its a good engine from a pilots POV but its definitely different to a none geared fan. You almost have to manage it like a turboprop engine. I suspect some of the issues are related to long time Jet pilots doing stuff that was deemed good practise on a old school jet engines and its not the way the engine was designed to be operated.

I know this doesn't belong here, but I know Alister follows this thread and I figured he'd be interested. Considering that this guy had less then 100 flying hours, it looks like he did a really good job, even managing to almost park the plane at a pull-off. Too bad the plane didn't have a horn as that might of helped with the people I'm sure he surprised when he passed over and then landed in front of them:

Terrifying Video Shows Plane's Emergency Landing On Highway As Cars Whiz Past

A novice pilot was forced to use a North Carolina highway as a runway after his plane's engine shut down.

https://www.huffpost.com/entry/plane-lands-highway...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

I did my PPL in Ormond beach in 2000.

Highways were the defacto option with engine failures. You just have so many of them in certain areas. And they are long wide and straight unlike other countries.

The traffic is going at the right speed to boot for most light aircraft landing.

There is double figures worth of highway landings after engine failures in the USA per year. It just this one was caught on video.

The lycoming o engine aero engine series is relevant to this thread. It was designed in 1955 and no real changes to it since and its still in production getting fitted to new aircraft. Twin magnetos for the sparkplugs. Survives abrupt cooling and students abusing it in the circuit. Not very efficient though.

They have to be overhauled every 1500/12 years hours operating though. Think the official time is less than 1500 but you can get an extension after certain checks.

I might add I never had an off runway engine failure in my 1100 hours of piston flying. Cancelled many flights with dodgy mags. Turbine engines are so much more reliable.

Turbines can have their share of problems. And those problems especially in the aircraft world, are many thousands of dollars more than comparing to the older piston engines of the past. How many millions does an average jet engine cost to overhaul? Big radial engines now are still under the 1/4 million range if even that much for an overhaul, and yes they still are on the job in many different areas of the world.

CF6 engine does 40,000 hours on wing.

https://www.geaviation.com/press-release/cf6-engin...

The first scheduled inspection overhaul is at 18,000 hours.

Meanwhile, check out this table for the R-4360 in a fleet of C97 aircraft. It shows in 1965 that only 12% of engines didn't have failures within their overhaul period.



You're doing well if you get to 1500 hours between overhaul.

http://www.enginehistory.org/Piston/P&W/R-4360...

So turbine engines require far fewer overhauls. Also, a turbine engine can do the work of 3+ of the largest recip engines which improves economy even more.

I'm a licensed pilot, typed on a couple of different hells, 2 piston, 2 turbine; (although not a professional one.. I probably have .1% of Alistair's accumulated hours) and based on that experience.. implying that piston aircraft engines are more reliable than turbines is yet another hilarious incorrect opinion to add to the growing list.

Airlines aren't in it for charity. If piston engines were more cost efficient, that's what they'd be using.

Never flown a supercharged petrol aviation engine.
Remember the theory stuff we had to learn about them..

The Lycoming o-235 was what I spent most of my uneventful time on. And we regularly used use extensions on them. They were needing a 50hour service every 7-10 days at the school I was instructing at even in winter in the north of Scotland Inverness.

Got loads of time on the Garrett tp331. Its pretty bullet proof.

Never flown the cf6 but you never hear anything about it.

Turbines are just so much less work to start and manage. The Fedec engines are much less than the old ones which were massively easier than piston.


And I don't place much value on flight hours. These days I pick up 8 hours in one day with 2 flights. Rotary pilots 8 hours is 16 plus approaches and landings and lord only knows about thermal cycles which is in my opinion is what kills aero engines along with miss handling. Which is another thing which helps with modern engines the pilot doesn't actually control it. They submit Thier wishes to the fadec. And it will sort it out for you. Old engines you could over temp them, shock cool them, over boost in a movement of one lever.

Tugboat, yeah all we have to compare to the modern day aircraft power plants turbine vs recip is the latest and greatest turbines to 1940's and 50's piston engines. Back in the days not long after chart was made, all engineering stopped on large aircraft piston engines. With the talk of electric motors in aircraft now, that would mean re introducing the propeller on airliners. Redesigning a high performance recip engine for large aircraft now could produce an engine that has 2x the efficiency of a turbine using way less of the same jet fuel, and producing more power than a battery laden aircraft would. I think they hate the idea of regressing back to pistons.

Quote (enginesrus)

Redesigning a high performance recip engine for large aircraft now could produce an engine that has 2x the efficiency of a turbine using way less of the same jet fuel

You do realize that if this was true (it isn't.. but I digress) and you did it yourself you could make hundreds of millions of dollars on this product

What's stopping you?

Propfan is a thing.

https://en.m.wikipedia.org/wiki/Propfan

As an aside they are going down this route with the latest generation of geared fan jet engines which the PW1500G is one of them the NEO and MAx have them as well.

The fuel savings are utterly collosal. Which was the main driver behind the MAX being developed in such a screwed up way.

As an example of real life fuel burns.

In cruise with a full load landing at max landing weight cruising at mach 0.78 we will burn 1800kg/hr. if we go economic mode around europe we can get 1600kg an hour with a full load in the back MAch .72 which is very near what we used to burn on the Q400 with 70 pax in the back at 1000kg/hr but with double the number of pax and much faster. The ATR might be an ugly uncomfortable, slow pain in the bum to everyone else, but it burns 600 kg/hr.

A 737 500 (which is nearer the same weight and capacity than a NG) doing the same thing approximate same weight will burn 2800 kg/hr. This is taken from the real life at work.

Some of that will be better aerodynamics because the neo and max don't get that marked a difference. But they still get a huge decrease in fuel burn but I don't have any real life knowledge that I have seen or experienced.

I do have real life experience a bit as ground crew with DC3's which were used for pollution control in Scotland. The R-2000 Twin Wasp engines were labour intensive from every level. You had 120 seconds after shut down to get 4 oil trays in otherwise it would sigh and dump its life fluids all over the apron and you would spend the next 3 hours scrubbing the concrete to decontaminate it. Pilot wise required a musician level of talent to adjust a power setting both in precision and timing. Flew it once but never landed it. And refueling it was a colossal pain , one of us used to have to go sit on the wing and hold the fuel gun in the hole. Do one wing then go do the other. Which may have just been a feature of that particular aircraft. And it uses utterly colossal amounts of petrol. From memory it took 3000 ltrs of petrol. Which gave it a range of 1300 nm in optimum conditions. low level it used to burn that in 2 hours spraying.

Just for fun when I started flying it I worked out the fuel burn per seat between the a220 and my old Merc E class 3ltr which I was getting 5.3 ltrs per 100km out of on long runs at 90 km/hr. It was getting very close km travelled per seat fuel burn. All previous types it was double at least the fuel per km per seat on previous types.

They want to add variable pitch fan blades to the next generation, but I suspect I will be in a box before they come along.

Funny story, my personal truck has an engine with a known problem. The main bearing webs crack at the outer bolt holes. The cracks eventually propagate into the water jacket. I like this example because the thicker fatter stronger aftermarket has always suggested solutions that never worked. In 2001 GM gave the molds to International to continue production. International's solution was to reduce the diameter of the outer main cap bolts from 12mm to 10mm and that solved a 20 year long issue with cracks.

Tugboat, what engine? So they essentially added more material to that area? Less clamping force?

Fuel burn ~ emissions, so I'd say its safe to assume aircraft and autos will both continue in the direction of less is gooder.

GM 6.2/6.5 diesel. No material added, they reduced the size of the bolts.

Effectively, material WAS added since the pilot drill for the 10mm tapped holes removed less material than did the pilot drill for the 12mm tapped holes.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

This was supposed to be my weekend project but apparently it's illegal to buy a camshaft bearing tool in California and I messed up the first bearing with my homemade tool.

Anyways first pic is my dead 6.2 block. Second pick is updated 6.5 block with smaller boots on the 3 center main caps.

Do note that the first engine was removed from service due to head gasket failure and that these cracks did not cause issues when running.

Quote (TugboatEng)

...apparently it's illegal to buy a camshaft bearing tool in California...

Please explain...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Prop 65

And exactly how does Prop 65 PREVENT you from buying a "camshaft bearing tool"?

https://www.p65warnings.ca.gov/

I've checked several online sources where camshaft bearing tools are sold and a couple of them mention a 'Prop 65 warning' and the best that I can see is that they might contain material which could cause cancer, but nowhere did I find anything that indicated that you couldn't actually buy one of these tool sets, just that you should be careful. BTW, they also warn you that you should wear safety glasses and avoid loose fitting close or open sandals when using the tool.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

If it doesn't have the label it can't be sold in California. Yes there are other options available but they have longer lead times/cost more. I went through this trying to get a fender for the truck. Driver's side can be bought in CA but passenger side cannot.

You don't take prop 65 warnings seriously, do you? They have to put the sticker on everything because it's impossible to prove that nothing causes cancer.

Are you sure that it's due to Prop 65?

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Yes, I have dealt with this before. Other sites list prop 65 specifically. This is what Amazon says.

So in reality, Prop 65 only inconvenienced you, since it didn't actually PREVENT you from purchasing a camshaft bearing tool.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

It has prevented me from buying that fender I want. I'm going to have to ship it to a friend in Washington and then drive up there to get it.

Cherry picking and blaming Prop 65

TTFN (ta ta for now)
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Did you try to buy both fenders from the same company?

I would say it's not so much Prop 65 that's the problem as much as it is that some companies are simply ignoring it. It's just that Amazon has taken it upon itself to comply.

And for the record, Prop 65 was just that, a proposition which was voted on by the people of California. In fact, in 1986, the Prop 65 initiative passed with 67% of the vote. And before you ask, NO, I did NOT vote for Prop 65. The reason was because this was on the ballot during the time when I had been transferred back to Michigan, which spanned the period from January 1986 until July 1987.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

IR, that's a different tool. It's much more expensive as well.

John, prop 65 is ever evolving and recently a lot of changes have been made.

Now we're defending prop 65 in this thread, eh fellas? What a world

Yeah Prop 65 a true engineering disaster, maybe it needs its OWN THREAD ( does social "P" engineering fit anywhere on this site?)? How and why does any form of industry stay in that state, when there are so many more friendly states?

And thank you JohnRBaker, that is what I meant. Since the tapped hole is smaller it essentially added more material to that area, and also since the torque is lower on the smaller bolt there is less strain from that.
That engine block is typical of many, too many corners cut in the design phase. That almost looks like it was never tested, it would have shown up during durability testing. It sort of proves they didn't do the correct things during the testing phase, too much dependence on FEA and not the real world.

Quote (enginesrus)

That engine block is typical of many, too many corners cut in the design phase. That almost looks like it was never tested, it would have shown up during durability testing. It sort of proves they didn't do the correct things during the testing phase, too much dependence on FEA and not the real world.

That engine first came to market in 1982. FEA did not exist, and the 'real' engineers you worship are the ones who put it out. So.

I think that it's quite possible that it was the result of an FEA analysis which led to the change in the bolt size, reducing it from 12mm to 10mm.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

I'd be curious to hear thoughts on the forces that cause the cracking. It's the only engine I know that does it despite similar designs.

It's a really good engine design if you have the right expectations of it. They're not the best engines for rebuilding because die catastrophically.

Quote:

IR, that's a different tool. It's much more expensive as well.

Yes, but the photos are almost identical so a copy, at worst, and obviously shippable to California.

In any case, Prop 65 is THE "get of out lawsuit free" card for any product with a listed chemical. Given that you all are ostensibly business friendly, I'm not sure why you think Prop 65 is a bad idea. If I were a manufacturer, for a measly upfront investment of printing a Prop 65 warning, I indemnify myself from any lawsuit claiming harm from exposure to a listed chemical in my product; it's a great bargain for manufacturers and retailers. Indemnification from exposure lawsuits for over 900 chemicals; whoot!

Indeed, I would think even if you didn't think you needed the warning on your product, you should go ahead and put it on the end-product and protect yourself from any subcontractor twiddling their product chemistry without telling you.




TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

So I have to pay $50 more for no damn reason because I live in California.

It's the same stuff, so nothing to do with California, per se; that's your chosen supplier being annoying. We can buy all sorts of stuff that's on the Prop 65 list without any issues, so don't rabble rouse unless you have proof. In fact, if the stuff on the list wasn't importable, you wouldn't see that warning every much, but every gas pump has that warning.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

Quote (IRStuff)

If I were a manufacturer, for a measly upfront investment of printing a Prop 65 warning, I indemnify myself from any lawsuit claiming harm from exposure to a listed chemical in my product; it's a great bargain for manufacturers and retailers. Indemnification from exposure lawsuits for over 900 chemicals; whoot!

Uh.. not only does Prop 65 not indemnify a manufacturer from hazardous exposure lawsuits, it also creates an ecosystem of lawsuits specifically related to compliance with the idiotic measure itself. It's the rare law that is actually bad for everyone.

Wait until California finds out how many face masks were sold without prop 65 warnings...

That crack is also on the other side of the hole, it looks like a combination of 2 different forces, and the lack of material cross section in 2 axis.

I don't think I can sue these guys for making the Siracha sauce too spicy and harming my throat.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

If I can finish this it will probably keep me from getting cancer. It's working for COVID so far.



That's a fermented capsicum pubescens sauce.

I'll ship some ir anybody is interested.

Does it come with a prop 65 sticker?

Quote (TugBoatEng)

That's a fermented capsicum pubescens sauce.

Did you make it from the Pubes or the Fruit?

It better come with ingredients that are known to the State of California to cause cancer.

Quote (IRStuff)

I don't think I can sue these guys for making the Siracha sauce too spicy and harming my throat.

D'oh, I should have done my own research before ingesting all that Sriracha. They warned me!

Seized spark plugs in aluminum heads. All such threads should be inserted like done with aircraft engines. Unless the spark plug threads have a corrosion resistant coating, seizure happens in time.
Using most of the normal anti seize compounds will not help, the heat can solidify some of them, and make it worse. There have been a lot of expensive repairs needed for something as simple as changing spark plugs.
In this throw away auto engine culture I'm surprised the spark plugs aren't just pressed in.

Anti-seize still works when it's solidified. It is a dry film lubricant, it only has the oil as a carrier to help it stock where you put it. Why people convinced themselves that anti-seize prevents corrosion I'll never know.

Good quality spark plugs do have a seize resistant coating on them.

Are you having issues with spark plugs seizing? I stripped one out on my very first engine. I've never had a problem since.

There are lots of things people may be doing to cause your experience. Spark plugs are seated plus 1/2 turn. This sets the crush in the washer. Do not use a torque wrench to install new plugs. If you're reusing the plugs, do not use the angle method as the washer is already crushed and you will strip the threads.

In all my years (decades) of dealing with spark plugs threaded into aluminium cylinder heads, I have experienced seized threads 0 times. I have experienced plugs that were tight coming out due to carbon build-up but this was due to use of non-OEM plugs that were about a thread or so too long (threads projecting into the combustion chamber).

I will grant that I have not owned, and will not ever own, a Ford 5.4 3-valve. (A friend of mine has one that belongs in a junkyard. He doesn't dare change the spark plugs, but there's so much else wrong with the truck, including terminal rust, that he's just driving it until it drops.)

There are lots of theory's out there about what temp the block needs to be when you change spark plugs.

I have never had an issue either or with glow plugs.

I have always loosened them off when the engine is hot then torqued the new ones up when it's cold on my own cars.

I don't think I have used anything other than NGK which could also be a factor.

The last time I changed any spark plugs was back in 2019 on my 2016 GMC Terrain, which turned-out to be a lot easier than I had expected. The dealer wanted something around $175. I found a YouTube video that showed the step-by-step procedure. Now this was a transverse-mounted 4-cylinder engine and the plugs were mounted straight out the top of the head. The coils were mounted on the plugs themselves, so you just popped them off and unscrewed the plugs. Now I did need to buy a new deep-socket made specifically for removing spark plugs (the only one I had in my toolbox was left over from my motorcycle days although I did have a 12-point deep socket that was the right size but wanted the dedicated 6-point with the rubber insert to hold the plug). That and four plugs, cost me a total of maybe $50. I already had a socket extension and a 24-inch breaker-bar so it was a quick, 40 minute or so job, from start to finish. Note that I used OEM ACDelco plugs and I did put anti-seize on the threads (it was recommended in the video) despite the fact that I didn't expect to change the plugs again, which I didn't before I traded-up to my current 2021 GMC Terrain.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Quote (JohnRBaker)

Now this was a transverse-mounted 4-cylinder engine and the plugs were mounted straight out the top of the head. The coils were mounted on the plugs themselves, so you just popped them off and unscrewed the plugs.

Most I've dealt with are similar; although in the case of my Mother's Toyota Rav4 you had to take off the air box to get to at least one of the plugs which is simple but adds several minutes to an otherwise five minute job. Similarly, my previous "Daily Driver" (Mazdaspeed 3) had a top mounted intercooler that had to be removed to access the plug wells. In both cases the manufacturer specifically recommends high mileage (75k mi for the MS3) rated plugs, presumably for that reason. Prior to working on either of those vehicles I always bought the cheapest NGK plugs available and simply expected to change them much more frequently; I don't know if I've altered that opinion for my Miata as it has no obstructions to replacing the plugs.

Why is anyone responding to this stupidity anymore. All this thread consists of is one stupid claim after another seeming posted on purpose to cause a reaction.

Spark plugs have come a long way in recent decades, not only in terms of intervals but also maintenance issues. Back when plugs had bases machined from heavy stock they'd often rust solid into iron heads, need a ton of force to remove, and end up removing the threads from the head. I do quite a bit of antique vehicle and tractor restoration, and usually use a ton of heat, lube, and vibration to ease old plugs out. Today's plugs are ultra-soft and coated so there's rarely issues removing them, even after 100k+ they come out with so little force that stripping the head is rare anymore even when the plug's threads strip out.

Yes, with my 2016 GMC Terrain, there were at least two large plastic 'covers' that had to be removed but it was only a five minute task.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

I lately have run into some badly seized spark plugs. All in aluminum, yes sometimes the normal tricks will work to remove them. But there is always the chance of breakage, then the length of time to complete the task increases dramatically.


( LionelHutz (Electrical)
20 Jul 22 15:14
Why is anyone responding to this stupidity anymore. All this thread consists of is one stupid claim after another seeming posted on purpose to cause a reaction.)

Wow !

You may have experienced seized plugs but your experience is likely the result of not following the manufacturer's recommendations and/or not using parts supplied by the manufacturer. This experience does not qualify as bad engine design.

What do you expect? You post a stupid baseless claim seeming to just get a reaction. Then, when there are no more comments you show up and post another stupid baseless claim just to stir the pot again.

Tugboat, this particular case is just trying to remove the plug for the first time ever from this engine. Never before changed plugs on this brand engine, I don't know the plug thread size, unsure about the cross section of material in that area of the plug, and the torque that would cause it to break off. Maybe someone else didn't follow the manufactures recommendations, or like many other things I have seen from the factory's maybe they messed up. I have seen in the past factory tightened 10mm bolts that required in excess of 150 lbft to loosen.

The N63 Hot Vee engine, many problem stories. Not very well thought out.

What is the trouble with a hot V? Caterpillar has been using the design successfully for 30+ years on their 3500 series engines.



Aftercooler is the yellow bit in the middle, you can see an intake tube bottom left and the rest is exhaust manifold. These engines run 1200°F exhaust temps continuously.

Hey look, the thread died for a week and now you're back again taking another poke at stirring the pot.

@LionelHutz

In his mind you've 'insulted' him personally to the level where he will just ignore you. He does the same to me after many responses to his threads questioning the logic involved.

Tugboat, 2 different engines and different applications. The N63 is known for problems, it is hidden under a hood with somewhat restricted airflow. Those big engines have plenty of airflow around them and are built 1000's of times better than the cast aluminum block automobile engines. Yes great idea if you can keep the heat away from the rest of the engine. I also understand they have some catalytic converters almost on the engine as well, I guess they wanted it cooking pretty good.

3500, did they ever work out the valve issues they had some years ago? The 3600's had some issues as well.

Quote:

Hey look, the thread died for a week and now you're back again taking another poke at stirring the pot.

To be fair, ~90% of this subforum is speculation based on popular media reports which are usually incorrect due to ignorance and/or sensationalism. Poke a bit of fun and don't take any of it too seriously.

Those intake ducts in my photo are aluminum. I don't understand what makes the N63 different, the hot V isn't the bad engineering decision. In these cases the failure is usually in the choices of elastomers/plastics. For what it's worth, those nuts and bolts you see are Inconel 660 and cost $20 each x ~150 of them per engine.

[link To be fair, ~90% of this subforum is speculation based on popular media reports which are usually incorrect due to ignorance and/or sensationalism. Poke a bit of fun and don't take any of it too seriously. ]Link[/link]

Most everything I post in this thread is of bad experiences of end users, with some of them backed up by lawsuit's.

I'm curious what sort of issues are the 3500's and 3600's experiencing nowadays? They were having problems many years ago.

The valves are a non-issue now. The 3500 is a very solid platform. Exhaust leaks are the biggest problem I experience nowadays. Cat has been all over the place with gasket materials. They use Parker EUI and ESI type gaskets or spiral wound. In all cases they spec stainless steel for construction which is subject to creep and take compression set as a result. Why they use SS gaskets and inconel fasteners, I'll never know.

So I am guessing they do not use those fasteners on mining truck engines or gensets?

Same fasteners on all engines. They went to v-band clamps for a minute and used Parker EUI seals but had problems with leaks because they used SS instead of inconel 750X. I'm sad they went back to the bolted flanges. The solution was simple. The v-bands really facilitated maintenance.

Quote (CWB1)

To be fair, ~90% of this subforum is speculation based on popular media reports which are usually incorrect due to ignorance and/or sensationalism. Poke a bit of fun and don't take any of it too seriously.

The difference is, in threads based on media reporting, generally the group does a fair job of recognizing that we're dealing with speculation, and generally the group also responds to new information in a rational way.

These threads involve no information at all, nor data of any kind. OP just makes stuff up basically and expects us all to agree with him.

Disagree with him enough, and ask enough questions about where he's getting his information from, and you'll get added to his personal 'ignore' list, as I have.

There is plenty of data, just look for it. I'm not spending time to do someones home work.
I have no ignore list.
My posts here are similar to others, it is to call attention to problems not try to solve them all.

While anecdotes are in fact data, they aren't enough to form conclusions. However, the purpose of this forum ks to share information to help solve problems. Some share information here to cause problems.

Data ? Is there any data on all the cam phaser failures in all the various product lines?
Honda is well known for the VTC actuator failure, that in the 4th generation didn't have a fix.
Here is some data, https://static.nhtsa.gov/odi/tsbs/2018/MC-10127348...

Data for Ford
https://static.nhtsa.gov/odi/tsbs/2021/MC-10199482...

I suppose there is plenty of data for the various engines and problems I have mentioned in the previous posts.

BMW data
https://static.nhtsa.gov/odi/tsbs/2021/MC-10201140...
https://www.classaction.org/media/urena-v-bmw-of-n...

The numbers for how many affected units in all the various cases would be next to impossible to discover. If they are not serviced at a dealer shop, then the numbers that the manufactures have would not be
very accurate.

Data for Hyundai
https://www.reuters.com/article/us-hyundai-recall/...
Is this all the sort of data you want? Or is it dealer and manufacture proprietary data you are looking for?
Like I have said the data is out there just look.

Quote (enginesrus)

I'm not spending time to do someones home work.

The burden of proof for your claims is on you, not the rest of us.