12 year old Yanmar GM2 - things to look for

dylanwinter

dylanwinter

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www.keepturningleft.co.uk
One of the Centaurs I am considering has a Yanmar GM2

the boat is ashore

I a told that it is a "good engine" - make of that what you will

estimated age 12 years old

the water pump has been changed recently

cutlass gland is supposed to be good too

I plan on going to see the boat and ask to hear and see the engine fire up from cold

any tips for what to look out for?

and... if I decide that I like the look of the boat but not the engine then how much is it worth as a runner?

the rest of the boat is roughish - Centaur sag, bent stanchions, inside is a pig sty, porta potty as it has been down the French canals so assume that the Yanmar has not had an easy life

the boat also has JRC radar on it?

Dylan
 
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Just to be sure ( to be sure to be sure), this is a raw water cooled GM20 and not a freshwater GM20F?

If it bangs up from cold immediately and idles happily, go for it

Maybe ageing rubber mounts, maybe declog the exhaust elbow, maybe the lattter is rusty too, but a nice lump for what you intend
 
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We had a 2GM on Kindred Spirit which was a great little engine.

Only thing I will say is that since it doesn't have preheaters it wasn't the best at starting in cold winter weather. Each year when we motored round for lift-out on a chilly January morning it would need to be spun up with the decompressors on, then have them dropped to start. Most of the year it would start on the button, almost before completing a full revolution. So don't judge this one too harshly if you go to look on a freezing day and it's reluctant to start.

Pete
 
My yanmar yse8 is 40+ years old and no problem running, starting etc. had spent 12 years immersed in water necessitating new rings and head gasket though.
12yo yanmar would be brand new in my world!

These things were originally designed to chug away all day so age is a bit immaterial. I'm told that Mr Yanmar was big in the early days of diesels but Mr Diesel had better publicity.

Nearly out of the Yanmar expensive parts frying pan but heading into the Volvo expensive parts fire now though.
 
SteveTibbetts said:
My yanmar yse8 is 40+ years old and no problem running, starting etc. had spent 12 years immersed in water necessitating new rings and head gasket though.
12yo yanmar would be brand new in my world!

These things were originally designed to chug away all day so age is a bit immaterial. I'm told that Mr Yanmar was big in the early days of diesels but Mr Diesel had better publicity.

Nearly out of the Yanmar expensive parts frying pan but heading into the Volvo expensive parts fire now though.
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my problem is that I am still frightened of inboards and the nasty kicking they can give you

of course I could buy this boat and motor it up and down the blackwater for a few days to see if it wants to break - if it will not break then I can keep it - if it breaks I can do the engine well bit

what worries me is that it might be fine until I get to some peaceful harbour in scotland and then have it decide to break - thinking bracket and Tohatsu as back-up.

Once bitten twice shy and all that

D
 
Have a look at the two engine anodes. They are not easy to get at but if the owner has been looking after the engine properly they will be in good condition. My 12 year old raw water GM20 has never stuck in reverse!
 
Simply cannot understand your paranoia about inboard diesels based solely on your one experience with a 40 year old past its sell by date example - and ignoring all the thousands of engines that operate satisfactorily. Never mind all the personal recommendations you get from folks here.

The Yanmar is among the best of its type and gives little trouble. Many are in use in charter boats in the Med and run over 10000 hours - so a trip up and down the canals is nothing - indeed the more they run the better they are.

My only concern would be neglect if the rest of the boat has been let go. However there is unlikely to be any mechanical harm. A change of filters and clean all the electrical connections to starter, alternator, switch panel and in the loom and it should be fine. As Pete says can be a bit slow to start in very cold weather as there are no glow plugs, but it does have decompressor levers so you can spin over rapidly before starting it.

It would be madness to take it out and replace it with an inappropriate outboard. By all means have an emergency outboard on a bracket - but to be honest, how many inboard engined sailing boats of any size have you ever seen that have an emergency outboard? Their owners can't all be wrong.

I would be far more worried about the "boaty" bits breaking on an old boat than an almost new Yanmar!
 
Probably won't get stuck in reverse but a bit of a lag going into ahead until the clutch grabs is more likely. Engine oil should be black, gearbox oil clean. Spinning it with the stop button out should show a marked difference between compressor levers up or down - no change is lack of compression. My 2GMF is now 32 years old and, with fingers crossed, touching wood, etc., is still chugging away after 4000+ hours.
 
Tranona said:
Simply cannot understand your paranoia about inboard diesels based solely on your one experience with a 40 year old past its sell by date example - and ignoring all the thousands of engines that operate satisfactorily. Never mind all the personal recommendations you get from folks here.

The Yanmar is among the best of its type and gives little trouble. Many are in use in charter boats in the Med and run over 10000 hours - so a trip up and down the canals is nothing - indeed the more they run the better they are.

My only concern would be neglect if the rest of the boat has been let go. However there is unlikely to be any mechanical harm. A change of filters and clean all the electrical connections to starter, alternator, switch panel and in the loom and it should be fine. As Pete says can be a bit slow to start in very cold weather as there are no glow plugs, but it does have decompressor levers so you can spin over rapidly before starting it.

It would be madness to take it out and replace it with an inappropriate outboard. By all means have an emergency outboard on a bracket - but to be honest, how many inboard engined sailing boats of any size have you ever seen that have an emergency outboard? Their owners can't all be wrong.

I would be far more worried about the "boaty" bits breaking on an old boat than an almost new Yanmar!
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I cried with frustration over that engine - I really cried. I was 57 years old and blub bing.

It cost me a £1000 and lost me 12 weeks sailing over two consecutive summers. . I promised myself that I would never, ever allow myself to get into the same position again. If some-one had walked up to me and offered me £5 to take the boat off my hands I would have taken them up on it. I was an utterly miserable time.

I am so much happier with my outboards. I feel safer than being dependent on one engine that has possibly been abused by another bloke. As for a 15 or 20hp outboard in a well being inadequate for a Centaur - well there is only one way of finding out.

My fear is that I will be up in orkney or Shetland and the thing will go pop

there is also the lobster pot factor.... and those scottish fishermen are blooming inconsiderate.

However, I will not remove a perfectly good engine but I will invest in a bloody good outboard bracket so at least I can have an engine I trust with me.

I got loads of very useful advice from MD1 lovers telling me what a great little immortal engine it was.

D
 
Our boat came with an old old 3GM20, starts first time and always has. Did have a few issues at the start -

1, Tried to clear out the raw water side of the manifold with a screwdriver as it was pretty clogged up and i was questioning flow from exhaust. Anyhow screwdriver proceeded to pierce what could of only been a wall of corrosion separating dry and wet chambers. > £750 to resolve
2, Raw water intake snapped off in marine engineers hand, £100

The previous owner of the boat was great at maintaining, slightly anal so i guess it was only time in a raw water environment that would cause these issues. Did once look at a centaur with a newish engine but closer inspection revealed a small crack in heat ex-changer so you never can tell by looks alone. I would have the engine started and run at near full revs for a while and see what happens - if the engine is sound it should be fine
 
surekandoo said:
Sounds like you'd be better off with a McGregor! Bloody great outboard on the back, sails too and lift keel. Answer to a maiden's prayer!

Shame about the looks though.

Surely you must give this option some serious thought?

:encouragement:
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a mac....

why not... if the price was right but they really hold their price

and I do not need a planing hull and the fuel consumption that goes with it

just one that plods along at 4 knots

D
 
dylanwinter said:
a mac....

why not... if the price was right but they really hold their price

and I do not need a planing hull and the fuel consumption that goes with it

just one that plods along at 4 knots

D
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Planing!!!?? Only if you open it up. Resist the temptation and do what I do with the car. Put a brick under the loud pedal!

Anyway I thought that Katie L was the bees knees. Why the need to change?
 
surekandoo said:
Anyway I thought that Katie L was the bees knees. Why the need to change?
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It's not a permanent change - Dylan has said he plans to die with (preferably not in) Katie L.

The Centaur is a means to an end for one summer of being bashed against Scottish harbour walls with four adults and a large dog on board.

Pete
 
Is it only me or are others thinking....

For goodness sake Dylan go and buy a boat so we can help you solve actual problems rather than "is it or isn't it", "will it or won't it", "shall I or shall I not".
All very hypathetical but doesn't seem to go anyware. Follow your instincts and make a decision. That's what most of us do.
 
surekandoo said:
Planing!!!?? Only if you open it up. Resist the temptation and do what I do with the car. Put a brick under the loud pedal!

Anyway I thought that Katie L was the bees knees. Why the need to change?
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Katie L is perfect - I shall own her until I swallow the anchor or win the lottery - actually even if I win the lottery I will keep her.

The Centaur business is because there will be four adults and a labrador aboard this summer - for a short while there will be five adults and two dogs....

aaaagh!

Katie L is perfect for one and the occasional two but having spent two weekends daysailing with four of us aboard - she was well down on her marks at the stern. She was crowded and overloaded

Back to engines.... Yanmar spares....is this engine fully supported and are they really, really expensive or just really expensive
 
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