Yanmar 2GM20 Cold Starting

[pip50]

Hello
Has anyone got any tips on cold starting a Yanmar 2GM20. Its fine when its warm but very slow to fire up from cold, its had a service and two new batteries. I have been told that they can be pigs to start as no pre preheat/glow plug. Is there an optimum position for the throttle? I do not want to over crank and let in water. Likewise I am reluctant to use Easystart spray.
Any suggestions?

 

[dukes4monny]

Hello
Has anyone got any tips on cold starting a Yanmar 2GM20. Its fine when its warm but very slow to fire up from cold, its had a service and two new batteries. I have been told that they can be pigs to start as no pre preheat/glow plug. Is there an optimum position for the throttle? I do not want to over crank and let in water. Likewise I am reluctant to use Easystart spray.
Any suggestions?

I find that mine needs about half throttle to get her going the first time on most days.
In the winter I find full throttle is required.........but I would turn it over for 5 seconds with the stop cable pulled out to get some oil around the motor first....

 

[Bilgediver]

Hello
Has anyone got any tips on cold starting a Yanmar 2GM20. Its fine when its warm but very slow to fire up from cold, its had a service and two new batteries. I have been told that they can be pigs to start as no pre preheat/glow plug. Is there an optimum position for the throttle? I do not want to over crank and let in water. Likewise I am reluctant to use Easystart spray.
Any suggestions?

Check the tappet clearances are OK and not closed up. Then as others say do not be shy on the throttle.

 

[Georgio]

Hello
Has anyone got any tips on cold starting a Yanmar 2GM20. Its fine when its warm but very slow to fire up from cold, its had a service and two new batteries. I have been told that they can be pigs to start as no pre preheat/glow plug. Is there an optimum position for the throttle? I do not want to over crank and let in water. Likewise I am reluctant to use Easystart spray.
Any suggestions?

I'm pretty sure the user manual states to use full throttle on start-up from cold. I have a 2GM and occasionally do this in cold weather, especially if not used for a few weeks. That said, in normally starts quite easily on about 60% throttle. In both cases be sure to throttle-back to a fast idle as soon as the engine is running, nothing worse than a stone-cold engine revving is poor guts out.

 

[nealeb]

I find that my 3GM needs a bit more throttle than the book recommends although you have to be ready to knock it back quickly once it starts. The other thing I do if I am starting from cold, especially if it's the first time for a week or two, is flip open all three decompressor levers, spin it up on the starter for a couple of seconds to get the oil circulating and some momentum in the flywheel, and then drop the decomp levers one by one. The extra engine speed gives a bit more compression, and even though it won't run on one cylinder (not from cold, anyway) the fact that it is firing keeps the revs up as you bring in the other two pots. I'm fortunate, perhaps, in that my engine is accessible through a hatch half the size of the cockpit sole so I can reach the decomp levers, engine control panel and throttle lever without moving. It also makes it possible to start the engine when the battery is so low that it barely turns the engine over with the decomp levers shut. Bit more problematic, maybe, if you have to be in the cockpit and simultaneously head-first into the engine via a small hatch under the companionway steps...

 

[fireball]

I'll go along with the 50-60% throttle from cold - bit more in the winter.

 

[srm]

According to a workshop manual I had setting full throttle with engine stopped gives more fuel for cold starting. When starting in air temp of around zero I would sometimes have to crank a couple of times. Taking the throttle back to idle then to full again while stopped made the second attempt more likely than just leaving throttle at full.

Do not crank for more than 30 seconds even if your batterys will keep the speed up as the starter bearings will fail sooner rather than later.

Is your starter up to speed? - mine got sluggish and replacing it made a great difference to the ease of cold starting in the winter.

 

[pip50]

Thanks for all of the advise, I am now heading off to the boat to give it all a try. If all else fails expect to see a Faultey Towers moment as I give it a damm good talking to!

 

[Bilgediver]

Thanks for all of the advise, I am now heading off to the boat to give it all a try. If all else fails expect to see a Faultey Towers moment as I give it a damm good talking to!

Don't swear at it if it doesn't fire up....Speak with encouragement or it will never oblige

 

[dukes4monny]

Don't swear at it if it doesn't fire up....Speak with encouragement or it will never oblige

Just like this?

 

[steve28]

If its still not playing ball then you may consider fitting a modified 12volt soldering iron to the inlet filter box, i have seen 40 watt versions used like a preheater.

The types i have seen have had the bit removed or cut off the the shoulder of the element that normaly has three screws holding the handle on is riveted to hole in the filter box directly opposite the inlet port. this is wired to a normal switch and is turned on before trying to start and whilst starting.

Steve