Hand cranking a 1GM10 - can anyone do it?

[jimmynoboat]

Can anyone tell me (preferably from their own experience) how to hand crank a Yanmar 1GM10?

I've tried several times to no avail. Here's what I've been trying;

Method 1:
Ignition switch on
decompression lever (or that thing you pull out to stop the engine) out
Crank like mad - almost impossible to turn

Method 2:
Ignition switch on
decompression lever (or that thing you pull out to stop the engine) out
little lever on top of engine lifted up with free hand
Crank like mad - spins easily
Get up a bit of speed then, when it's not looking, decomp in and lever down
NOTHING but a bang on the head as I loose balance followed by extreeme tinitus ... oh! ignition off

Having had battery charging problems recently it just occured to me that this would be a handy little trick to know.

 

[ancientsailor]

From memory, your close to it on method 2. I think you may be shutting off the fuel?

Engine controls:
Ign on and engine stop to "run" position (this may be fuel cut-off)
Neutral

At the engine:
Decompression lever (the little one on top of the engine) over - this way resistance reduced
Wind her up
Spinning fast
Decompression lever over

We went aboard a part-flooded Contessa 26 where sea-water was over the top of the only battery and part-way up the side of the engine.

Pumped her out and she started a treat

 

[Ubergeekian]

Method 1:
Ignition switch on
decompression lever (or that thing you pull out to stop the engine) out
Crank like mad - almost impossible to turn

The engine stop thingy cuts off the fuel - it doesn't do anything to the compression. The lever on the head is the decompressor.

Method 2:
Ignition switch on
decompression lever (or that thing you pull out to stop the engine) out
little lever on top of engine lifted up with free hand
Crank like mad - spins easily
Get up a bit of speed then, when it's not looking, decomp in and lever down
NOTHING but a bang on the head as I loose balance followed by extreeme tinitus ... oh! ignition off

No need to do anything with the "ignition". All it does is power up the starter and alarm circuits - the engine will run quite happily with it switched off, and you don't get the alarm buzzer screaming at you as you try to start it.

I had this problem a couple of weeks ago. My mooring was moved (at my request) and it looks as if the chap moving the boat left the echo sounder on. Which wouldn't have mattered if I hadn't left the battery switch at "Both" so the solar cell would keep both topped up.

I completely failed to start the engine by hand. I had an assistant doing the decompressor, but even getting it going at a fair lick I never got it through a single compression. Every attempt just bounced it back. I'd be seriously worried about a chauffeur's fracture if it managed a backfire.

I think the flywheel is simply too small for hand starting. Diesels need to be able to store enough kinetic energy to take them over at least one compression, and the Yanmar 1GM just doesn't. Perhaps a strong person with good access could do it, but I wouldn't even bother trying again. If I ever replace it, the new engine will be one which can readily be hand started. Meanwhile, I'm wondering if a combination supplementary flywheel / starting handle will work - though it might be a pain to carry and fit.

 

[prv]

Not pulling the engine-stop lever would be a good idea if your goal is to start it.

Pete

 

[wiggy]

Come on it's not that hard. This is what I do- Ingnition on and in neutral with no throttle. Remove companionway steps to get best access to engine. Decompressor up. Wind like mad with thumb tucked in (to avoid breaking it in backfire situation). When top speed is achieved let the decompressor go and hope for the best. I usually get mine going second attempt.

 

[jimmynoboat]

Not pulling the engine-stop lever would be a good idea if your goal is to start it.

Pete

Doh!

I always pull on the brake levers when I'm pedaling my bike uphill too! Sometimes life is just too easy:¬)

 

[Tranona]

Tried on many occasions to start mine by hand. Only once lucky - but ran backwards as it bounced over when I dropped the decompression lever.

 

[agurney]

Come on it's not that hard. This is what I do- Ingnition on and in neutral with no throttle. Remove companionway steps to get best access to engine. Decompressor up. Wind like mad with thumb tucked in (to avoid breaking it in backfire situation). When top speed is achieved let the decompressor go and hope for the best. I usually get mine going second attempt.

I find I have to keep winding after dropping the lever otherwise it just bounces on the compression as there doesn't appear to be enough mass in the flywheel.

If your battery is low lift the decompression lever, turn the engine on the key and drop the lever when it's up to speed.

A portable car battery booster will start a 1GM10


Alisdair

 

[prv]

Has anyone ever come across a spring-starter for these engines? I know they're used on portable pumps and the like; the emergency generator on Stavros has one and that engine's about six foot long. But actually fitting one to a GM might be tricky without modifying the flywheel housing.

Pete

 

[snowleopard]

I have 3GMs with hand crank. Never managed to get one over a single compression. With multi-cylinder engines you drop one decompressor then do the others when it is running - in theory.

BTW you need 3/4+ throttle to start a GM series - no glow plugs.

 

[Ubergeekian]

A portable car battery booster will start a 1GM10

In the end I jumped mine with a borrowed battery from the marina next door...

 

[PeteCooper]

I have started mine by hand on many occasions. I have somebody in the cockpit leaning over and lifting the decompressor lever. I then crank like a madman and once it is spinning as fast as I can manage, if I ask the helper to drop the lever, and away it goes. The only time I have actually needed to do this because of a flat battery I failed miserably - the boat was bouncing about in a big swell and I couldn't get myself steady enough to crank it. Once we had sailed in and moored I was then able to start it by hand.

 

[penfold]

Everything should be as it is when doing an electric start except the decompression lever; typically 1/2 to 3/4 throttle to avoid racing as you won't have to scramble to throttle back if it goes. Then apply the armstrong starter; get it spinning as fast as possible, signal for the glamorous assistant to release the decomp lever and keep bloody cranking! Half the time people who struggle to handball a grumpy diesel make the error of slacking off when the lever drops, which is not the way to do it; this is often exacerbated by the boatbuilder installing the engine with the crank level with the floorboards or some such making it a crippling exercise strictly for Quasimodo lookalikes. As noted the Gucci way of doing it would be to get a spring starter, but they are bloody pricey.

 

[Ubergeekian]

Half the time people who struggle to handball a grumpy diesel make the error of slacking off when the lever drops, which is not the way to do it; this is often exacerbated by the boatbuilder installing the engine with the crank level with the floorboards or some such making it a crippling exercise strictly for Quasimodo lookalikes.

I would have found it a heck of a lot easier if the engine turned the other way, too.

 

[andygc]

Tried on many occasions to start mine by hand. Only once lucky - but ran backwards as it bounced over when I dropped the decompression lever.

Ditto. And running backwards destroyed the foam air filter.

 

[tobble]

I agree with all in favour - perfectly possible, especially for left- handers

it does take a lot more effort when it's cold (the weatehr and the engine, that is...)

The only thing I realy have to add is make damn sure the handle has engaged propperly on the spiggot - I didn't once, just as it got up to speed it slipped off, and the cam shape on the end suddenly became a menacing claw shape as it swung up, gashed my eyebrow open and almost knocked me out...

thankfully there were people around as I had just been re-launched, and the nurse who stitched me up gave me something to keep my good eye on.

 

[mikemonty]

Can anyone tell me (preferably from their own experience) how to hand crank a Yanmar 1GM10?

I've tried several times to no avail. Here's what I've been trying;

Method 1:
Ignition switch on
decompression lever (or that thing you pull out to stop the engine) out
Crank like mad - almost impossible to turn

Method 2:
Ignition switch on
decompression lever (or that thing you pull out to stop the engine) out
little lever on top of engine lifted up with free hand
Crank like mad - spins easily
Get up a bit of speed then, when it's not looking, decomp in and lever down
NOTHING but a bang on the head as I loose balance followed by extreeme tinitus ... oh! ignition off

Having had battery charging problems recently it just occured to me that this would be a handy little trick to know.

Preferably ignition on.
fuel stop not... errr... stopped.
decompression lever up (decompressed).
In neutral and half throttle.
Edited to add - Thumb on same side of handle as fingers - unless you enjoy pain.

Crank as fast as you can.

It doesn't matter at which point you drop the decompression lever as long as you are STILL going as fast as you can (if you ease up because you think your'e part in the proceedings is done you will lose momentum and fail).

The 1GM doesn't have the mass to keep going if it is being cranked slow, and you (unless you are part-way to a gorrilla) don't have the strength to crank it over TDC without losing compression. So the only way to get enough momentum is SPEED, lots of it.

If I go all Zen on it - don't even bother to think about how you can get enough power into your cranking by muscle alone you'll just tense up and waste effort - you need to concentrate on getting RPM up - If it was a bicycle it would be more like a spinning session than a hillclimb.

Depends on your layout whether you get someone else to handle the decompression lever - but don't even bother to try timing it - your arm will have to be going so fast that shouting NOW! and relying on your assistants reactions - and your own judgement of where the crank will be is pointless.

When you shout NOW! it should be at the point when you think you are about to peak.(OOOhhhh Errr....! RPM of course)

And have a dry towel standing by because you will have done this while wearing oilskins and will now be soaking with sweat.

 

[eagleswing]

'that thing you pull out to s top the engine....'

....."Method 1:
Ignition switch on
'decompression lever (or that thing you pull out to stop the engine) out.....'

as noted above -this 'thing that you pull out to stop the engine ' is a cable attached to the throttle mechanism on your engine. (as an aside it is a good idea to keep this cable properly greased both at the cockpit end, and on the engine , or this cable may 'freeze' when you need it most to shut off your engine...) so your pulling OUT the engine stop cable completely shuts off your fuel supply. as the above post notes, you need 3/4 throttle to supply enough fuel to start the engine...

 

[wiggy]

BTW you need 3/4+ throttle to start a GM series - no glow plugs.[/QUOTE]

Mine starts bettter with no throttle-worth a try

 

[elton]

I suffered an inguinal hernia trying to crank my MD2B over

Best of luck