Yanmar 1GM10 Reliability Issues - Advice Please

[selkie2]

My Yanmar 1GM10 has been playing up. This engine has previously been very reliable but the boat has been out of the water for a couple of years and since launching last week my engine keeps cutting out. Sounds like a fuel issue of some sort.

Prior to launching, tank was drained and refilled. Oil and filter was replaced, as was battery. Fuel system was bled and fired up easily and ran smoothly but after 2 hours of perfect running (on delivery voyage from launch site to mooring) it cut out. Sails were hoisted and, after fuel system was bled again, the engine restarted and ran smoothly and powerfully until we arrived at the pier heads of our destination harbour when it cut out and we were unable to start it again. Arrived at mooring within tight little harbour under sail !

We emptied water collector -fair bit water found mixed with fuel, changed fuel filter (seemed clean) and checked that fuel tank breather was not blocked.

After the above actions engine now starts first time, runs for 10 mins then cuts out. These tests have only been performed at the mooring at relatively low revs. I am somewhat reluctant to leave mooring and give it a proper trial in case I end up stranded.

I would be grateful for any thoughts/suggestions as to how to remedy the situation.

[GordMay]

Greetings and welcome aboard the CF, selkie2.

[Boracay]

Is it possible that you have a blocked breather hose, or a tiny air leak in a fuel hose?

[s/v 'Faith']

It sounds to me very much like an air leak somewhere.

When the motor stops running, and you bleed it do you get bubbles?

I would look at the fuel lines very carefully... if you have rubber hoses know that some diesel additives can make them get funky, especially where they connect to the hard lines. If you can twist them on the barb the clamps are likely too loose... or the fuel line has degraded and is allowing air to be drawn in.

Also look carefully at all the connections.. were the crush washers replaced on the banjo fittings>? Are they all snug?

How about the 'O' rings on the (racor?) filter?

A couple ideas, hope something helps.

Post and tell us when you figure out what it was.

[selkie2]

Thanks for replies to date.

Blocked breather tube was a thought but alas no, breather tube to tank seems to be patent.

No obvious bubbles when bleeding the diesel but the first time that the engine conked out bleeding seemed to do the job....but not the second time. Next visit to Selkie I will check out the various hose attachments in more detail.

It might be a simple issue of oxygen starvation because the main air intake to the engine compartment comes from a cockpit locker and this had a polystyrene box pushed up close to it. This has now been removed.

Next time I'm aboard I will give engine a good run at higher revs and see what happens.

I will update thread after next attempt.

[bill good]

Fuel system Found water - might be diesel bug in lines. Fuel lift pump would need checking. Could set up small gravity feed tank from a small container to check how the engine runs on alternate fuel source. Also would overhaul or replace water pump before going too far if sea water cooled. The fuel filter bleeds are prone to damage. Check air filter had the felt from this area down the inlet & held inlet valve open.

Regards Bill Goodward (2 X 1GMS )

[glenn.225]

selkie2
Just a thought but were the tank and lines cleaned. I have often come across cases where paint chips or leaves (anything flat) gets sucked up against the fuel pick up and cuts off fuel. When suction is stopped the dirt floats away and then gets sucked up again after a short while. You can also get very tiny pin holes in intake line that will allow air in but fuel won't leak out. We used to have a fuel cap with a tire valve stem in it and would pressurize system to 5 or so PSI to help find fuel leaks.

Glenn

[selkie2]

Great suggestions guys. I am so impressed by the number and speed of responses to my post.

It will likely be next weekend when I get to the boat again so I will fill you in with progress after next visit. Boat moored 100miles away from where I live. But Hey, absence makes heart grow fonder does it not?

Boat was out of water for 2 seasons. Initially, tank was kept topped-up to brim to avoid condensation but I wanted to run engine last year so, for fear of diesel bug, tank was drained (by syphon - cant get enough of that sweet sweet taste of diesel!) and a few litres of fresh diesel poured in for running engine. This year drained tank, again by syphon, so I doubt if got it completely empty, before filling to brim again so no-doubt condensation over the last 12 months is likely to be source of water found in the water trap.

Tank is fairly small and plastic and always refuelled through filter so hopefully little crud lurking in the bottom.

Incidentally, the diesel that I drained a year ago (probably 18 months old and without any diesel bug treatment) looked ok so I ran it in my landcruiser without ill-effects!

Best wishes and thanks to all of you.

[selkie2]

Visited Selkie at the weekend and all was well. Checked everything over and all seemed well. Engine started first kick and remained running. Hopefully problem has been solved.
In retrospect I think the problem lay with the partially blocked-off air intake caused by my own carelessness but It has been fine to go down all the other routes to find a cause for the problem as I'm sure that the experience will stand me in good stead in the years ahead.
Thnk you all for your helpful advice.

[bigpuff]

talking about yanmars,iv got bene 411 and conected to the keel bolt is an earth wire going back to the house battery bank.whene i looked the ot

[hunter marshall]

I'm considering buying Yanmar's 1GM10 model motor for use on 28.5' (6.5 ton) British built 'Sea Rover' sailboat. Any advice on if this is a suitable engine for this vessel for long planned circumnavigation? Please advise about suitability and engine pricing? Or other motor that might be a better option, such as betamarine? Thanks, C.Hunter/eom.

[selkie2]

Hi
My first thought, upon reading your post, is that 1GM10 seems a bit lightweight for what you have in mind. It's a great little engine for getting my 26.5ft 2.5 tonne boat in/out of harbour and for short passages but I suspect it would be underpowered to get your boat out of any significant trouble. However, if you are a die-hard sailor who wouldn't consider using an engine unless for berthing and wants a lightweight diesel then you probably wouldn't go far wrong.
I think that if I was in a heavier boat and trying to get off a lee-shore then I'd want something with a bit more wellie!
Regards

[jimczarnowski]

Hi all. This looks like the right place to ask this question..

I have a 1GM10 that has been well maintained in my Ericson 26, but on a recent trip back from Catalina, where it ran at smoothly at 2900 RMP for 20 hrs, it suddenly dropped to 2000. I replaced both fuel filters, the air filter and checked the intake in tank for clogs. All was pretty clean. Next, I re-primed and that seemed to fix it for a few hours. But then, drop to 2000 max RPM, and running rough, like it was fuel starved. I have re-primed a couple more times with the same results. Any chance it is my fuel pump? Or air getting into the line? I do recall bubbles coming out when I primed. I also cracked the nut at the injector and turned the engine over by hand (with the decompression lever pressed) to bleed that section. I was surprised to not see much fuel pumping out around this nut. Should it bleed like the normal bleed screw when the manual fuel pump is actuated? Thanks!

[Greg Y]

I just repowered my 30', 7500 lb sailboat. I had a Volvo, 2 cyl 10hp. I put in the Beta 14. OMG!! It is awesome. Smooth, high rpm...boat zips along at 6 knots with a killer wake. Makes me want to buy waterskies!! I cruise in the Pacific Northwest, Vancouver area. We commonly see 2knots of ebb/flow and 20knots winds. This engine just bucks right through everything.

I spent a lot of time researching and the balance tipper for me was how many hits you get when you google "yanmar XXX engine problem", "Volvo XXX engine problem" and "beta XXX engine problem" with the model numbers inserted.