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cranking a diesel engine by hand

cranking a diesel engine by hand

cranking a diesel engine by hand

(OP)
Is it possible to star a heavy diesel engine by hand say a 2.5 DI
I knows in days gone by before the starter motor they used to start petrol engines by attaching a hand crank to the cam shaft
Someone told me that with a diesel you will not get the engine to go fast enough; is this true or not?
If it can be done where can I buy a hand crank from (the crank would have to have a centralfugal clutch inside it so as when the engine spins and runs the end with your hand on dose not spin as fast?
And where would you attach this tool to?

Thanks
batista230

RE: cranking a diesel engine by hand

No, you won't be able to. In order for the engine to start you have to be able to turn it over at a speed fast enough for it to run, probably 60-100 rpm or so. In order to do that you have to overcome the compression ratio of the engine, which on a diesel is rather high.

In the past it may have been possible using decompression valves, but a modern automotive engine is unlikely to be fitted with them.

Typically starter handles fitted into a crude ratchet on the crank nose, which may pose difficulties in the case of a FWD car.

Cheers

Greg Locock


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RE: cranking a diesel engine by hand

Hand cranking went out of style _instantly_ when a practical alternative was offered, because of a high incidence of wrist and arm trauma.

WRT to hand-starting a 2.5DI, I'd bet that you could restart one that was already warmed up, at considerable risk to limb if not life.

Mike Halloran
Pembroke Pines, FL, USA

RE: cranking a diesel engine by hand

With de-compressors yes, without forget it.
Some boat motors have de-compresssors and the proceedure is/was to get the thing turning over as fast as possible on the hand crank, then trip the de-compressor off. If you were lucky it woulf fire off, if you were not it would slowly chuff to a standstill, and you would then start the whole proceedure again, until it fired off or you were exhausted.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

RE: cranking a diesel engine by hand

We used to hand crank Lister engines - the crank handle was on the camshaft, so the crank ran double speed. I'm left handed, and it was a mission for me to start the singles - open the valve lifter and start cranking, get it going as fast as you can and then drop the lifter....but I had to change hands to do that. If it didn't start, it was downhill from there as I got weaker and weaker. Strangely, the twins and triples were easier to start than the singles - more flywheel weight? and being able to drop a valve one at a time.

RE: cranking a diesel engine by hand

Fixed Base Engine?? and do you have some room around the engine?

Use a hand cranked aircraft engine inertial starter... I have one that found its way into my family junk "treasure" pile decades ago.. a Bendix Eclipse Series 6 hand crank inertial starter. The torque limiting clutch on it is set to 550 ft lbs and capable of starting aircraft engines up to 2500 cu inches per the Bendix Spec... able to store a considerable amount of human sourced energy in a small package... the whole unit is about 8 - 9" in diameter and about 8 inches long..

They were built in hand cranked and combination hand crank, equipped with a small electric motor and using a fairly small battery, to spin the flywheel up to 10-11,000 rpm. The flywheel stores enough energy which is transmitted through a 100:1 ratio stacked planetary gear set to turn the engine over...

Hand Cranked Inertia Starters
http://www.pilotfriend.com/aero_engines/aero_eng_i...

http://www.youtube.com/watch?v=WkPFRpbSU9o

http://www.youtube.com/watch?NR=1&v=3zXkVQnVmu...

Electric motor version to spin flywheel up to speed...
http://www.youtube.com/watch?v=GrrTtbA8Ujs&fea...

This is 1925 era technology (when they were first designed and built) and the Wright R975 and Pratt & Whitney Wasp Jr R985 radial engines were probably the first major large scale use of these starters...

Old technology has a way of coming back.. FIA 24 Hour Endurance racing has sanctioned use of Hybrid energy storage systems, Porsche (and I think Audi) with KERS (Kinetic Energy Recovery System) (flywheels), Toyota using electric motors and super capacitors..

RE: cranking a diesel engine by hand

My '38 Ford Ferguson 9N has a hand crank. Even though it's only about 28 HP with 4 low compression cylinders, let me tell you I will do anything to avoid having to crank it by hand. I can't imagine hand cranking a diesel.

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

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: cranking a diesel engine by hand

I have a benz 240D with an 2.4 l OM616 IDI diesel, easy enough to turn over by hand w/ a 1/2" ratchet. I'd be cautious about starting anything w/o a ratchet or 1 way clutch on the crankshaft, don't know why hand cranks didn't include some mechanism to let the crankshaft overrun.I don't think this engine would kick too hard on a reluctant start, between the 15W40 and the other piston compressing behind.

That being said, it needs more speed and heat to get an ignition event than a gasser which will at least backfire for you at low revs. If the compression event is not fast enough, you will not stay far enough ahead of heat transfer and leakage to get a compression ignition. A reluctant diesel start can seem like forever when the battery is doing the work, forget a person. One winter, 08-09 the glow system was bad and I idled it at work until the air temp was >15F.

It roll starts well enough, I'd estimate 3-5 guys and/or a sufficient incline if not warmed up.

Now that I think about it, I would start it with a bicycle on a dare.

RE: cranking a diesel engine by hand

LadaTrouble (Automotive)
That brings back memories. My dad was an electrical engineer. In the late 40's and early 50's in the UK., not all of the farms were electrified, so the farmers used Gen sets. These were usually Lister or Petter, with the majority being those Lister single cylinder twin flywheel diesels. So I would get to crank while my dad manned the de- compression lever. It was amazing the number of times we turned out at 4-00 am to " I can't get my generator to go, and i've got to get the cows milked", to find out that the farmer had simply let the unit run out of fuel, and had then not bled it properly. Then when he could not get a start, had called the " experts".
Mind you when you got it sorted, there was nothing more satifying than that first thud followed by a cloud of black smoke then the Thump -----Thump -----Thump---Thump --Thump _thump-thump thump of that engine building speed against those fywheels.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

RE: cranking a diesel engine by hand

A 1902 Oldsmobile had an inertia crank start. The carank got the flywheel spinning reasonably fast then either the flywheel engaged or more likely the valve train engaged and the inertia in the flywheel started it. Not exactly a new idea, BUT it was spark ignition.

The feature of cranking spark ignition is that you MUST retard the spark to ATDC it avoid a broken arm and the possibility of the engine running backwards.

Another feature of crank starting is as pulling up to TDC, if the compression makes the load to high, you simply hold against the compression for a second or two while some pressure bleeds off past the ring gaps or wherever, then flick it over TDC.

While I am sure that a diesel injection timing can be retarded,I would think that the extra complexity of that along with the extra compression and the requirement that the heat and compression be retained long enough to fire the charge would strongly mittigate against cranking a diesel.

Regards
Pat
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RE: cranking a diesel engine by hand

The ones I remember were small single cylinder diesels with decompression. The actual crank slotted into the front of the flywheel which had a loose spiral bayonet type fitting so once the flywheel speed was more than that of the hand crank, the handle would slide out of the socket to prevent arm damage.

Still, if it didn't start the first 2 times of trying, I would be knackered and probably wouldn't get it going for a while.

RE: cranking a diesel engine by hand

Once the speed was over about 80rpm I flicked the decompression lever and as my focus went from cranking to leaning over to switch the lever, the flywheel would overtake my crank handle speed and disconnect it.

RE: cranking a diesel engine by hand

You have to keep cranking until the in-cylinder temperatures rise enough to allow combustion. That could take minutes, but it will eventually get there. I remember well the cold-start tests of IDI diesels in my student days. 60s of cranking, loads of smoke and then finally the engine would pull its own weight.

- Steve

RE: cranking a diesel engine by hand

I believe most instances of broken bones occur due to an engine firing before top dead center and the crank getting pushed in reverse. I guess that a ratchet mechanism on the crankshaft could prevent injury.

RE: cranking a diesel engine by hand

Pat,

I don't think ignition BTDC is a problem w/ diesels when starting.
1. The fuel charge is introduced over a fairly long interval. On mercedes 61x diesels, I think the fuel injection occurs from 23* BTDC to 15 after. So the 'bang' at autoignition temp is not a big one, unless ether or WD40 is misted in.
2. The early ignitions seem partial anyways. The bump you hear and feel from the partials is distinctively different than the first 'clack!' that throws it over and gets you going. The 61x prechamber includes the glow plug, and also a metal ball suspended in the path of the injector jet. The glow plug and the ball I think respectively give and sustain heat in the chamber that promotes a pilot ignition event.

RE: cranking a diesel engine by hand

Yes, it is possible. With the engine on car use the leg crank: give the car a push, then jump in and clutch 2nd gear.

RE: cranking a diesel engine by hand

>>Yes, it is possible. With the engine on car use the leg crank: give the car a push, then jump in and clutch 2nd gear.<<
My choice in a pinch. Needs a bit more speed than a gasser tho.

RE: cranking a diesel engine by hand

They don't kick back on ignition, but from compression - it's like hitting a brick wall. You have to use a decrompressor, and have to get it spinning fast enough for the flywheel to take it over compression. Forget all you know about hand cranking a spark ignition engine, you will never get one to turn over and start with just one turn of the crank handle.

I learned to kick start old British singles in my youth - it's all technique. I was thinking of putting a Lister single into one of my BSA's, but there is no way you could start one with a kickstarter. A motorcycle kickstarter is geared down, the Lister is geared up with the crank handle on the camshaft.

RE: cranking a diesel engine by hand

Many years ago I often had to hand-crank a generator powered by a three-cylinder Lister. It always started quite easily - but this was in the northern tropics of Oz - so the ambient temperature was always very hot.

I think the Lister was in the 2 to 2.5 litre capacity range. But it had a decompressor and (I suspect) a very heavy flywheel - so you could really build up quite a lot of momentum before disengaging the decompressor.

RE: cranking a diesel engine by hand

My first cars were mostly 1960's UK makes and most had a starting handle but it was extremly difficult to get them to start using it. The usual problem was that you only needed to try it on a frosty morning with a flat battery so everything was against you from the start. The last car I had with a handle was a 1500cc Moscovich which was an awful but fun USSR saloon. The compresstion ratio was about 9:1 and that was difficult to turn over under any circumstances never mind to actually start.

John

RE: cranking a diesel engine by hand

Going off on a tangent, anybody know how huge marine diesels are started?

RE: cranking a diesel engine by hand

In some cases at least, they have a smaller (e.g. ~12L, ~300hp) diesel engine that gets started first, which is then used to start the main engine.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

RE: cranking a diesel engine by hand

"How are marine diesels started"
Youtube is full of examples......

EMD Engines.. air starter motors....
http://www.youtube.com/watch?v=hFVJ9Lhhm0I
http://www.youtube.com/watch?v=yvdocH6jP_Y
http://www.youtube.com/watch?v=aanSnb6FrjU&fea...
http://www.youtube.com/watch?v=W-VlTKL7U6A&fea...

EMD also uses battery powered, twin electric starter motors on locomotives

compressed air, cylinder injected via timing distributor...
http://www.youtube.com/watch?v=iZr2umGKQXg&fea...

RE: cranking a diesel engine by hand

Nice. Watt Linkage at 5:10 in the last one.

RE: cranking a diesel engine by hand

When I worked on projects in the Oz bush many years ago all of our bulldozers were started by first starting a small two-stroke petrol engine which was then clutched-in to start the diesel bulldozer engine. The diesel engines started readily enough but the two-stroke "starter motor" engines usually required about half an hour of pulling on starter cords and much bad language.

RE: cranking a diesel engine by hand

My first boss told me that in the days of the Model T, farmers were told to have their wive learn how to crank the engine. In case the crank spun backwards and broke her arm, she could still do house work with one arm, while a farmer would have difficulty working with one arm in sling!

True story!

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RE: cranking a diesel engine by hand

Back in the 90s when I worked on sheep stations out in the boondocks we had to hand crank large single cylinder engines at the start of the working day, everyday. Most (even the diesels) were easy to get going, flick on the decompressor, crank the handle for about 30 seconds (these engines had huge flywheels so it took at least that long to get some speed up), flick the decompressor off and away they would go, if a second attempt was needed then you had another go, the 3rd attempt was best done by someone else. There was the odd story of the crank handle getting stuck in its slot every now and then, apparently the best course of action when this happened was to run away from the beast and watch from a safe distance until the handle let go and shot up through the roof (or side) of the shed, they say that 2-300 meters is the usual distance that the handle is thrown.

RE: cranking a diesel engine by hand

Now I have to try that.

RE: cranking a diesel engine by hand

i used to work on old cars for a living.
you develop lots of muscles hand cranking those old 6:1 compression model T fords etc.
gotta be arnold swartzenegger to hand bomb an automotive diesel.

RE: cranking a diesel engine by hand

It is quite possible given a proper setup. The early days, the king's of hand starting were volvo marine diesels. They had a compression release lever that you would flip and it would hold the exhaust rocker down just a little bit and hold the valve off the seat thus zeroing out your compression and allowing you to spin it up. It had a crank handle with a directional catch so cranking it would catch but once the motor spun faster than the crank, it would push the handle out. For this to work, you need a huge flywheel. I think to start a 16hp volvo they ran about a 130lb flywheel. Old Wisconsin motors have the same thing going on.

Second method is the one used by old listers in emergency life rafts. Air starters. They all ran air starters with accumulator tanks. The passengers would operate a foot pump to pressurize the accumulator. Once pressurized, hit a switch and poof, the thing started.

Finally. If you've ever watched the discovery channel shows, the miners along the amazon where they pan for gold. They carry around a 5L international tractor motor. When they need to start it, they've taken a steel wheel, welded it to the crank hub. Put a pull cord wrapped around it. Now with it about 6' high on a bank. 3 of them jump off the bank holding onto the rope and pull start it. I called BS as well but hell it works.

Moral of the story. Don't over think it.

RE: cranking a diesel engine by hand

Normal cranking speed on a VW TDI is around 300 rpm, but in cold weather, I've had mine slow down audibly much lower than that on the first compression stroke, then the moment the fuel hit the glow plug, the first power stroke got it going. Good luck doing that by hand - with 19:1 compression, it's not going to happen. And if you have battery power for the glow plugs, you have battery power for the starting motor.

We've bump-started them in warmer weather as someone mentioned above, because of a weak battery, by having someone push and then dropping the clutch in 2nd gear. You need to get the car going at 15 km/h or so in order to do this successfully ... and that's a chore for the person pushing in itself, unless you have a little downhill to help out.

Hand crank alone? No way.

RE: cranking a diesel engine by hand

I like that jump off a cliff technique, true cave man engineering.

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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: cranking a diesel engine by hand

You can hand start anything with the correct mechanism. The air pump and accumulator being one end of the scale and the jumping off the embankment being the other. You just need to build, store then suddenly release energy. Spring powered impulse starters for motor mowers being a very common example at one time.

Regards
Pat
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RE: cranking a diesel engine by hand

Direct hand starting of diesel engines is not normally recommended unless there is a decompression system and/or a feature like Gardner engines had which increased the tappet clearance on the inlet valve so that it closed at BDC instead of 25 degrees ABDC, thus giving you a full cylinder's worth of trapped mass and thus a high effective CR under cranking conditions. This feature may make it harder to crank, but it improves the end of compression temperature, and it is the speed over TDC that is important in starting a CI engine. That is where the big flywheel is very helpful, as on the Field Marshall tractors.

Other hand cranked starting aids include the Simms Spring Starter, see British patent GB1107521 filed in 1963, now manufactured by: http://springstarter.com/default.asp and http://www.ipustarting.co.uk/en/products/spring-st... and http://www.startwell.com/

Alternatively, there is the Simms Inertia Starter, and also the Bryce Handraulic Starter, now made by Prestolite: http://news.prestolite.com/drupaldocs/Handraulic%2... They are all excellent choices if electric starting is unavailable or unreliable.

PJGD

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