1GM10 Behaving Oddly!

[Deleted]

Does anyone have any experience with a Yanmar GM10 engine? This is the most reliable engine I have ever come across. Just get it over compression and it starts straight away whether it's the middle of Jan or flaming June. It still starts easily now, but lacks power. There is a noticeable drop in revs at tickover if the battery has been used for lighting etc when staying aboard and the alternator is working hard to recharge it, and if the battery is really low the engine doesn't have enough power to rev beyond tickover at all.

The oddest thing is that on a few occasions when it's been ticking over for a while it has suddenly revved up on its own for no apparent reason, before returning to tickover.

Does anyone have any ideas? Or any experience of the best place to get a Yanmar engine a thorough service at a reasonable price?

[allan]

Julian, do you have any smoke at any time when you are having problems? Often problems with diesels are caused by injectors, if this is the case, you can get them checked at a commercial engine company. If you go to a yacht place you will pay at least double.
Allan

[Deleted]

Yes, smoke, most definitely! As always the engine started first time over compression even after that really nasty freeze up, but the first thing I noticed was that it was smokier than I remembered from the previous year. Clouds of blue stuff!

I'm not exactly sure what you mean by a commercial engine company Allan. Could you give me an example? And how do I get the engine to them? If they are not a yacht place surely they won't have watery access.

Julian.

[vikingsmb]

Julian,

when were the fuel filters last changed?, as they could be clogged thereby preventing derv getting to the engine, or as allan said it could be the injectors.

cheers
rob

[Deleted]

The simple answer is I don't know, Rob. I only bought the boat at the beginning of last season and haven't done anything to the engine. I suppose it is due for a service now anyway! Perhaps I should get them to change the fuel filter and check the injectors at the same time.

Only thing is I have no previous experience of getting work done on a marine egine and don't know where to go, or what the procedure is. Do we take our yachts to them? Or would they come to the club? Do they do it in situ or have to take the engine out? (That sounds expensive!).

Julian.

[Deleted]

We have the 2GM20 on Enigma. I have done my own servicing so far and been going up the learning curve. It's a semingly unburstable engine but rather than exchange notes on the forum, if you want to chat then we are on board during open day tomorrow. Call in if you want.

Hayden

[allan]

May 6, 2011 22:18:22 GMT @julianc said:

I'm not exactly sure what you mean by a commercial engine company Allan. Could you give me an example? And how do I get the engine to them? If they are not a yacht place surely they won't have watery access.
Julian.

Julian, I was trying to think of a correct name and "commercial engine company" was the best I could do! Basically, all diesel engines have injectors and they can be tested to ensure they are producing a cone of liquid. Lorries for instance routinely have them checked. Marine engineers just send them to the same place and add a nought to the cost. You just take them out and take just the injectors to them.
It sounds like if you were to do a service things would get much better for very little cost. It will only take you a couple of hours. Since you have owned Katy, Chausey has had about four services, just filters, oil, anode and heat exchanger cleaning.
Allan

[duncanhall]

Julian

Manana has a 1GM engine its only 6 years old and I have a full manual for the boat if that helps. I expect it could be downloaded. I had it serviced in Gloucester last year. It costs a couple of hundred.

I had my Volvo in Ardua serviced at Cardiff Marine Services, That cost about £230. I just took them the boat. However there were other issues!

[Camelot]

There's an excellent injector servicing place in Cardiff. Though to be honest I last used them about 5 years ago. Excellent service, and it really made a difference to the engine. Cost then was £11 per injector (julian, you only have 1 injector). If I were you I would have this done, and change the oil, oil filter, primary and secondary fuel filters, cooling water impellor, and cooling water system anodes. Your air filter is of a cleanable type, so this needs a wash out. All this should cost in the region of £75 if you do it yourself.

Name and address of Injector service place:-

FUEL INJECTION SERVICES LTD
UNIT 2, THE STONEYARD
NINIAN PARK ROAD
CARDIFF
CF11 6HE
02920 225909

If you need some guidance give me a call.

[Deleted]

Thanks to everyone for their input. Think I am now fully prep'ed to have a go myself!

[Deleted]

just a thought Julian - on reading Martin's problems with diesel bug - have you checked the fuel / pipes before it gets to any of the filters. If it develops slowly, it would initially just reduce flow ..and therefore give no power as you have said. I'm not sure I would recognise it, but it looks as if several others would.

[Romantica]

Julian,

If your engine is starting and it is only has one injector, it is unlikely that there is anything wrong with it.

From your original post
"The oddest thing is that on a few occasions when it's been ticking over for a while it has suddenly revved up on its own for no apparent reason, before returning to tickover."

If this happens when the throttle lever is pushed over, then this would indicate a fuel blockage.
The least expensive course of action would be to replace your Fuel Filters and check what condition the old ones are in , following replacement.
Check the fuel that will be lodged in the filters for colour and debris.

This would certainly be the cheapest way forward.
Hope this advice assists you
Cheers
Steve D