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cranking a diesel engine by hand

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Batista230

Batista230

Civil/Environmental
Dec 11, 2010
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GB
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
 
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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
 
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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
 
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"How are marine diesels started"
Youtube is full of examples......

EMD Engines.. air starter motors....

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

compressed air, cylinder injected via timing distributor...
 
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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.
 
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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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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.
 
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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.
 
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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.
 
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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.
 
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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.
 
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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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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: and and
Alternatively, there is the Simms Inertia Starter, and also the Bryce Handraulic Starter, now made by Prestolite: They are all excellent choices if electric starting is unavailable or unreliable.

PJGD
 
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