How to hand crank start a Yanmar 2GM20

eebygum

eebygum

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Does anybody know how you hand crank start a Yanmar 2 GM20 ?

I know you need to switch the water cock off (until started) but what else ? I seem to remember you raise the compression levers but now sure what you do next.

The reason for the question is ..... we were heading off to Ireland at the weekend from Anglesey and decided to turn around half way and head for Holyhead in the rising SW F6-7. About 8 miles from Holyhead we noticed a voltage drop on the instruments and decided to start the engine .... no joy the starter battery was also drained (loose alternator belt and poor connections proved to be the problem).... I spent a very unpleasent 20 minutes down below leafing through the engine service manual trying to find the cranking instructions but could find nothing ! Fortunately the wind vane was wizzing around in 24-28 knots and after an hour had put enough charge back into the batteries to get started.

I promised myself when I got back that I would find out how to start the engine by hand cranking !

Thanks in advance.

Cheers
Andrew
 
I know you need to switch the water cock off

why do you need to do that?

I think you lift the decompresser as you say then spin the engine as fast as you can then drop 1 of the levers and hopefully she will fire on that one then drop the other lever...and your running!....hopefully....but I'm no expert.
 
you can start any diesel using the following method.

fFrst turn the engine over WITHOUT THE DECOMPRESSORS ON . when DTC is felt on one cylinder move the hand drank to either 10to or 20past (which ever feels most comfortable). Now put decompressors on and crank over smartish . When at sufficent speed------- at the chosen 10to or 20 passed whilst cranking drop the lever . Starts everytime . Try it /forums/images/graemlins/cool.gif
 
Amazing that you have one of the few 2GMs to be fitted with a starting handle dog at the front of the engine. Normally, something else gets in the way, as I remember. Is this a direct sea water cooled version, a 2GM20 as opposed to a 2GM20FW?.

Anyway, whatever. The sequence goes like this:-

Get wife to locate and be familiar with operation of the de-compressor levers. She lies on her stomach in the cockpit with arm stretched down to previously mentioned parts. If she can't reach, you've married an inadequate and all is doomed to failure before we start!

YOU (and preferrably, NAY, ESSENTIALLY, a beefy friend) are in saloon having once won a sheet winch winding gorillas' competition and ready to explode in gyratory testaronic fervour. Set the throttle lever at the usual starting position plus a nudge.

Wife is briefed to drop one lever ONLY (or you and friend are in for at least one session of physio!) at your grunt when you and friend are about to reach a climax of your gyratory efforts. (YES, the whole thing sounds a little erotic, doesn't it?)

After ensuring that above will happen and starting with both levers in de-comp position, taking a deep breath and looking each other coldly in the eye to confirm commitment, you and friend embark, in a POSITIVE manner on your gyratory task WITH VIGOUR!

When point of climax feels imminent you drop the nod to missus and instantaneously wind with yet another 20% of effort, being positive rather than negative (or all is lost) - going on until the beast complies by firing.
(Hopefully)You both sink back (you and friend that is, of course!) like a post coital Odysseus and Penelope on his return from Troy to the satisfying sound of yet another Yanmar, paddy field irregation engine, bursting into life. (wife is now insructed to release second lever)

If result is total mechanical inactivity, promise friend a really good dinner and a bottle of Chateauneuf du Pape and after performing Agincourtian re-stimulatory re-briefing, start previously described procedure over again.

That's it. The book SAYS that it's possible and I've done it only twice and the other time was on a Volvo 2002 I must admit it is KNACKERING so I would make sure that the battery is ALWAYS OK if I were you!

Steve Cronin
 
Also don't let your thumb go round the cranking handle coz if it kicks back you'll have trouble hitch-hiking or counting up to 10. Keep both manly chins clear of the gyratory procedure or you'll be drinking beer through a straw. Make sure the ignition is on too. Or marry a Russian weightlifter.
 
[ QUOTE ]

Fortunately the wind vane was wizzing around in 24-28 knots and after an hour had put enough charge back into the batteries to get started.

[/ QUOTE ]
What do you need an emgine for when you've got plenty of wind to sail with.
 
[ QUOTE ]
...sounds a little erotic, doesn't it?

[/ QUOTE ]
It may sound erotic and you'll certainly need a lie-down afterwards but if you're able to do anything more than gasp for breath you should be wearing your underpants over your tights! I've tried to start my 3GMs that way and never succeeded yet and I'm not exactly small! I tell myself I could do it if I was adrenaline-fuelled when being driven onto a lee shore.


A serious point though. On the GM series only the raw water cooled versions have a hand crank and with these the water flow from the pump is very much lower than on the fresh water cooled engine so you'd have to crank for a very long time to fill the exhaust system. As long as you have a proper waterlock in the exhaust there is no need to turn off the seacock. If you have a saildrive it is VERY dangerous to turn on the seacock with the engine running as you would have to lean right across the engine with the risk of catching clothing in the belts. A man was killed that way a few years back.
 
I agree with Snowleopard. Despite my 2GM20 being a good starter with the key, and good access to the starting handle, I never succeeded in hand starting it, so my advice is don't bother trying. Luckily I never encountered a situation which demanded hand starting. OTOH my previous Yanmar YSE8 hand started easily.
 
I have added a cable that allows me to short across the splitting diode. That puts the domestic bank in parallel with the start battery and gives the extra half a volt that is enough to get me out of trouble. I am also fortunate in having a spare engine so if one has a flat battery I can usually get the other going and link the batteries.
 
[ QUOTE ]
I have added a cable that allows me to short across the splitting diode.

[/ QUOTE ]

You'd be better to have a paralleling link across between the batteries. The diameter of charging lead in not enough to take cranking current. We have a link made of 50sq mm battery cable with crimped and soldered tags. This closes the two batteries via a standard, red flag battery switch. If we couldn't start our 50hp Volvo by battery we would be stuck.

Steve Cronin
 
[ QUOTE ]
I agree with Snowleopard.

[/ QUOTE ] And I agree with earlybird. I don't think there's a chance of me starting my 1GM10 with the handle. The main reason seems to be that these engines have quite light (very light?) flywheels so there's insufficient moentum to help you carry past TDC and get it to fire. I once sailed a boat with an old Bukh with a huge flywheel which you could start by hand but probably only because the flywheel helped.
 
Thanks, Steve I never knew crank starting could be that much fun !

Yes it is a 2GM20, sea water cooled with the starting handle at the front. Not sure there is enough room to get the girlfriend lying down on the floor in the Contessa 26.

Cheers,
 
I don't think there's a chance of me starting my 1GM10 with the handle. The main reason seems to be that these engines have quite light (very light?) flywheels so there's insufficient momentum to help you carry past TDC and get it to fire.

But isn't that why you keep powering the crank to add power/torque.?

i have 1gm10 and look forward to trying to hand start it!...erm but first i have to rebuild the thing:)
 
Lucas used to make a Spring starter that you coulsd literally wind up like clockwork and then engage to fire up the motor- A clever idea imo but since Lucas were (unjustly?)famous for their indifferent reliability (Lucas-Prince of Darkness),there is a certain irony there.
Famous tail of the Frenchman who when faced with duff batteries at the end of an ocean trip,arranged a rope wound round the flywheel and up through the companionway hatch andfed out through a deck block to the boom.When he gybed the boat-Voila !
Of course if that went wrong I expect there is enough energy there to yank the front motor mounts apart ! /forums/images/graemlins/laugh.gif
 
I can start my 2gm20 every time hot or cold with the starting handle, its quite easy when you know how.
Make sure the water is off as everyone has already mentioned, next put the throttle to full in neutral.
Put both decompression levers up and wind the engine over about six times, slowly will do.
Then for for it and flip one decompression lever, if your good get the lever when the handle is at about five o clock position.
If you have very flat batteries then i would suggest a slightly different option that being turn the main battery switch to off, start engine as normal and wait for the engine to warm up a bit, then stop the engine and put the battery on again and start again by hand. The reason being is that the alternator takes a fair amount of your spinning effort away.
 
You have just described.....

... a classic "How to destroy your Alternator" scenario.

Any idea as to why your boat has a little plaque stating "Do NOT run engine with batteries dis-connected"?

Running it until operating temperature is reached should do fine.

Steve Cronin
 
Get her into the quarterberth then and remove the inspection panel. Perfect excuse!

My God! Modern youth!!!

Steve cronin

/forums/images/graemlins/wink.gif
 
Sound preliminary advice is

1. Is there enough room to swing the handle without cracking your knuckles
2. Do you have a heart problem

If yes to any DON'T
 
Re: How come....

[ QUOTE ]
...that you can't start a 1GM10 yet I DID start my 2GM20?

How do you suppose that is?

Steve cronin

[/ QUOTE ]
Maybe your compression is a bit down.
 
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