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Fun Thread on another site. "How long will an average automobile engine run without oil"

Fun Thread on another site. "How long will an average automobile engine run without oil"

Fun Thread on another site. "How long will an average automobile engine run without oil"

(OP)
And think of the old hit n miss engines of the past, with oil cups, oil pressure was at a low ebb in those days.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

Bearings make their own oil pressure.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

In high school autoshop we tried to blow up a Honda sedan, one of the first ones into the country. It was one of those little boxy cars that looked like an Austin Mini Cooper. It had a motorcycle engine in it, 600cc IIRC. We fired it up and bricked the gas pedal. It floated the valves and peaked out with a horrendous amount of noise. After about 3 minutes of this we realized it could be a long wait and unbricked it. Pretty quickly it was decided we could drain the oil and shorten things up quickly. We shut it off drained the oil and started it again. Re-bricked, it ran for about 15 minutes valves floating until it actually ran out of gas. Told by out teacher "you can have only this gas", about a gallon, we decided to up the anti and drained the coolant too.

No oil, no coolant, we tried a third time. This time about 10 shocking minutes into the run something caught fire. The engine continued unabated but the a fire was not going to be allowed by our teacher and we had to shut it down and extinguish the fire before things went completely sideways.

End result.. an engine can potentially run a very long time with no oil. It was felt that the engine being pretty old was a big help in the process of not breaking and that a new 'tight' engine probably wouldn't last long, but that was one test we couldn't afford.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

most experiments i have seen were with quite worn down engines at no load. quite a few of them did run for quite some time. if they were stopped before they seized up, and later on filled with oil and coolant however, they were quite a bit more rattling then before the experiment, so running without oil and coolant had taken its toll....

i guess the amount of load is the important factor: if there is hardly any load temperatures will not rise very fast, so the conditions that would make seizing up likely may not be reached any time soon. in your car the coolant temperature rises quite fast after the start to about the optimal temperature, but under normal driving conditions it may well take about 20 minutes before the oil temperature stabilises. thus, a temperature rise within a journal bearing may take quite some time given sufficient play and low load.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

I've been a member of several car clubs where running a junk engine with no oil and betting on the time until catastrophic failure was an annual fundraiser. Its often 5-15 minutes.

Not to sidetrack, but engine oil pressure is irrelevant vs flow. Many racing engines for example run at zero pressure but with a large volume of flow, generating pressure being unnecessary work. OTOH generating steady pressure is a great indicator of flow, and I'm among those who hate the newer vehicles being sold without an oil pressure gauge having owned many classics and clunkers with questionable flow.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

Well, here's my personal experience:
Many years ago when I was a youngster, I borrowed my brother's VW Scirraco. I was driving in city traffic when the water temp light came on. I figured I'd limp to the next gas station and check it out. About a block later the engine seized. Turned out it was the oil pressure light, not water temp. The "while you wait" oil change place had stripped the drain plug and stuck a rubber plug in instead. It fell out, stupid youngster didn't recognized the little picture on the warning light and the engine promptly froze. Big brother was not happy!

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

Quote (CWB1)

run at zero pressure but with a large volume of flow

Sure about that?

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

Back in about 1970 in the UK, it was late one Sunday night out in the country after the pubs had closed and I was about 10 miles from home and motoring briskly to get there when I heard a slight noise that I did not recognize. Looking down at the instruments, I was just in time to see the oil pressure needle drop back to zero. Looking in the rear view mirror I was able to see in the headlights behind me a great cloud of smoke. When I pulled over to check under the bonnet/hood of my Jowett Javelin, I found that the flexible oil hose to the oil cooler had split so that the whole contents of the sump had been pumped onto the road.

What to do? Well, I needed to get home and had no way to call a tow truck anyway, so I just got back in and motored somewhat less briskly the 10 miles home. The engine made it back without incident, and the next morning I put on a new hose, refilled the sump, and drove the 30 miles up to London to work. The engine survived that incident without apparent damage, and I attribute that to the aluminium crankcase which may have dissipated the bearing heat reasonably well, and the fact that the engine was moderately high mileage so not "tight". I assume that this would not have been possible, and I would have been dead in the water if the engine had hydraulic lifters.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

(OP)
I've read all kinds of stories about oil loss and how long the engines ran even under load. One guy claimed I think it was 90 miles of driving with out oil. And other cases as well as personal experience with engines seizing from lack of oil and running for unknown time with out it, and then adding some oil and push starting to break the crank free, and doing this all multiple times, with no known ill effects from it. So just because it seizes does not mean that is the end of the bearings or other parts. Hydraulic tappets? No big deal they can go a long time with out leak down. Just letting the average engine sit for a month or more no banging and clattering from tappet leak down at start up.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

In the world of 2-stroke dirt bikes, if the engine seizes and then frees up later you took out the top end. If it seizes and stays seized you lost the crankshaft.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

(OP)
The problems I have seen in oil less 2 stroke gas engines is mostly scored piston skirts and cylinders, most small ones run in frictionless bearings and they seem to last for quite awhile with no lubrication, even longer if there was no fuel air in the crankcase washing them dry.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

My brother ran my Zundapp 2-stroke dirt bike out of gas on the trails and got some from someone riding a 4 stroke. It seized in short order. I replaced the piston, rings and wrist pin, started it up and heard the most horrible knocking, shut it down and went to bed. The next day he got home from school earlier than I did and rode my bike again, supposedly not noticing the knocking. I nearly killed him when I got home but tore the engine down again instead. This time it was evident that the big end bearing needles were breaking up and getting between the head and piston. Ouch! So now I needed a new head, piston, rod & bearings. Took me months to get the parts from Germany. Eventually I got it running again but that bike became a parts bike for a newer one.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

(OP)
So then it looks like plain bearings are the better choice for a shaft running with very little lubrication.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

Plain bearings require a steady circulating supply of oil, rolling element bearings do not.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

(OP)
Not from what these folks are saying about the 2 strokes they've dealt with. I've seen and experienced cases where the plain bearings have run for a long time with out lube.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

There is a reason most 4-stroke dirt bikes run ball bearing main and roller bearing rod bearings. They're heavier and have a shorter life expectancy than a journal bearing which are negatives but they can handle oil starvation better during some of the extreme lean and pitch angles seen while riding off-road and during the moments of zero gravity while the bike is airborne.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

I've seen may TV infomercials, where an engine is filled with snake oil, then emptied and run dry. The ability for it to run dry is credited to the snake oil. It's impressive if you are expecting (like most people) it to fail in seconds.

Steve

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

(OP)
Some of the so called snake oil has real good EP qualities, I'm not real sure how EP lubes work with or helps soft bearing materials? Though in areas where a strong EP lube is needed it works great.







Edit to add an S.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

The engines on the snake oil adds are being run unloaded. Add a load and the results will no longer look so good for snake oil.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

We ran an Indian Thunderstroke 111 with no oil pump/minimal oil supply as a durability test.

It ran for a quite a few hours, lifters clattering away, with no lube, but it ran, very high temps in the pan.

That engine is indestructible!

www.auto-scape.com

Sideways To Victory!

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"


I remember an advert in the UK in the 1960s with an old car , touting Molyslip a Molybdenum disulfide compound , They had put this in the engine oil run it for a while , then drained all of the oil out.
They then drove this thing up hill and down dale until the engine seized. It took ten miles.
B.E.

You are judged not by what you know, but by what you can do.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

We had a similar stunt many years ago in Australia. I think the product was Nulon. A car was treated then driven something like 1000 km with no oil.

Found this.

"In 1983 Nulon modified a Holden Commodore engine which had hydraulic lifters to solid lifters, so it would work without oil
They ran the car around for 5k with the E30 additive and then at a public press event, drained the oil from the sump.
The car was then driven by a motoring author and some other guy (neither from Nulon) from Sydney to Melbourne
At all times the oil light was on showing no oil pressure
The car/engine successfully completed the 1031km journey

This "no oil" demonstration has been done often (in the past) in the USA at motorcycle events.
They show an engine mounted on a test frame running, then drain the oil and restart the engine.
Sometimes these demonstrations include actually riding a bike with no oil.

The Briggs and Stratton company decided to perform a back to back test.
They ran two new engines on test frames for 20 hours, one with a (unspecified) PTFE oil additive
They then drained the oil from both and ran the engines for a another 20 hours
Both engines survived this ordeal - so they were run for a second 20 hour interval without oil
Both engines were then torn down and inspected
both engines suffered from scored crankpin bearings,
the engine treated with the additive also suffered from heavy cylinder bore damage that was not evident on the untreated engine.
"

je suis charlie

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

(OP)
gruntguru, good stuff about the Briggs Strattons, is there a good place to find that information? So where those aluminum cylinders? And what year did they do that? So a total of 40 hours run time with no oil? Where they loaded on a dyno?
Even so major engine loading or not there is still a lot of load from running. It would be nice to see the details of that test.

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

Had a motorcycle buddy who'd built up a 600CC 2 stroke dirt bike. I helped him over to a big dirt lot in the industrial park to give it a few laps on the 1/4 acre. We got it out of the truck and he started it up and let it idle for about 2 minutes. He then started around the perimeter of the little lot at a brisk pace. He made it about 1/2 way across the lot before the back tire locked up on him almost dumping him. He stared at it for a minute lifted the seat and then I could hear intense air darkening swearing. Turned out this was one of the early two-strokes with the little oil tank that mixes automatically with the fuel and he'd failed to fill the little oil tank. The top end was toast.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

(OP)
No more editing ??????? In my above post where is were......................

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

A Google search brought up this book. Link

je suis charlie

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

enginesrus; this site, rather generously, allows us about 48hrs to edit a post compared to the usual 1hr of most forums. I suspect you waited 49 hrs...

Dont woorry, we all no your a engineer an donot expekt u two be able too speel.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Fun Thread on another site. "How long will an average automobile engine run without oil"

No names No pack drill.
Many years ago I was driving a 5 ton truck for a city electrical department. It was an old GM product with a 6 cylinder engine.
Our truck came back from a scheduled oil change and we went to work. We never drove very hard or very fast. We spent most of the day parked.
On the third day, in a fit of boredom I checked the dipstick. ( Due too union jurisdictions I was not supposed to check the oil.)
Bone dry.
We headed to the shop. After a quiet conversation the sump was filled with oil and nothing was ever said for many years.
I don't remember why there had been no indication of low or no oil pressure.
The truck had never used oil and after the event it seemed to run as well as ever.
It may have had some oil but it took a lot of oil to top it up.
When every one is in coverup mode a lot of details are not determined.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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