Yanmar engine

Caer Urfa

Caer Urfa

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Had a few engines in my time but anyone know what sort of gearbox comes with a Yanmar 30 hp engine, do Yanmar make there own gearboxes ? or are they Hurth, ZF ,PRM etc

Any experience of how reliable Yanmar engines are and are they expensive to repair

also anything to watch out for if viewing a 80's engine with 700 hrs on the clock
 
You should be able to find a manual on-line.

My gearbox is by a patnership between Kanzaki & Hurth, but I'm not sure if that would apply to the 30hp engine. I've a 4JH.

I've found mine pretty reliable (that's bound to curse it). When I read some of the posts on Volvo engines I realise I've been lucky having a Yanmar. Apart from anything else, self-bleeding is a dream when you have to change a filter at sea.

Parts are expensive in Europe. I've not had to do anything major yet (touch wood).
 
Is it a 3GM? I've got one and (touch wood) it's been pretty good. One of the better engines out there, IMHO.
Various versions available, both fresh and raw water cooled, and some variants arrived in the EU for final assembly (presumably for tax reasons)- these have some subtle differences including, from memory, a different make of water pump and thus a different impeller.
 
If it 80s probably a 3gm30. I have the 2gm20 with a Kanzaki gearbox. I was told by a Yanmar agent engineer they are bulletproof. I've never had any trouble with it
 
Spyro said:
If it 80s probably a 3gm30. I have the 2gm20 with a Kanzaki gearbox. I was told by a Yanmar agent engineer they are bulletproof. I've never had any trouble with it
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It's an 1984 engine (about 700 hrs on it) so guess you are right, I have not seen it so doing my homework of reliability and what to look for when viewing

Thanks everyone
 
Caer Urfa said:
It's an 1984 engine (about 700 hrs on it) so guess you are right, I have not seen it so doing my homework of reliability and what to look for when viewing

Thanks everyone
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Pretty bullet proof, although only 700 hours in 34 years would worry me - that is 20 hours a year. It will probably be sea water cooled (heat exchanger engines are suffix F for freshwater) so pay attention to the cooling system as it tends to clog up with salt deposits, particularly if it is not run hard to get it hot.
 
3GM30 here with a Kanzaki gearbox. Seems to work well especially considering the engine miles I do.

Changing the oil is a pain, but then it's only 0.3l so no huge deal.
 
Cheers Tranona made a note of your comments ref salt/sea water 'I assume' the letter F will be on the engine plate,

not viewed this boat yet so will have a good look plus also note other comments as 'for armed is for warned' :),
 
Caer Urfa said:
Cheers Tranona made a note of your comments ref salt/sea water 'I assume' the letter F will be on the engine plate,

not viewed this boat yet so will have a good look plus also note other comments as 'for armed is for warned' :),
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Be pretty obvious as it will have a heat exchanger if it is fresh water cooled.
 
Fr J Hackett said:
If it is out of the water check and replace the rear crankshaft oil seal.
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Or if it's not leaking leave it be. Why would it need to be out of the water for that? Definitely check and replace the exhaust elbow if you can't determine it's age. I'm sure it will have been replaced at sometime at least once.
 
The original 3GM30 engines are fitted with a higher spec gearbox than the twins and singles - I can't remember exactly the codes that differentiate them. The later 3YM30 engines are fitted with the same gearbox as the twins in the range. The only gearbox issues that have come up a few times is that the cones occasionally need lapping in. thought to be caused from ahead to astern or vice versa without letting the revs drop, it manifests itself by the cones slipping and a folding prop will "bang" as the blades set, then back off and set again every few seconds.

Sounds like something is hitting the hull! Costs about £80 for the bearings which are worth swapping out when the box is open. Otherwise it's a couple of gaskets-worth to fix.
 
Mikedefieslife said:
3GM30 here with a Kanzaki gearbox. Seems to work well especially considering the engine miles I do.

Changing the oil is a pain, but then it's only 0.3l so no huge deal.
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Sorry to be a Pedant, but surely you mean 3 litres, not 0.3 litres?

I would be seriously worried with that tiny amount in the sump........................................
 
Nudge said:
The only gearbox issues that have come up a few times is that the cones occasionally need lapping in. thought to be caused from ahead to astern or vice versa without letting the revs drop, it manifests itself by the cones slipping and a folding prop will "bang" as the blades set, then back off and set again every few seconds.

Sounds like something is hitting the hull! Costs about £80 for the bearings which are worth swapping out when the box is open. Otherwise it's a couple of gaskets-worth to fix.
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I am having exactly what you describe with my folding prop. It has got worse since I got a big clump of fishing net and ropes around my prop a few weeks ago. Since then I have noticed that after reversing and putting the gear in neutral, the prop continues to rotate.
I am expecting a mechanic aboard tomorrow. Do you think that it will be a matter of lapping the cones as you describe, or is this more serious?

Edited to add: this is on a Yanmar 3JHE, I do not know the type of gearbox.
 
Have a 1995 3gm30 kanzaki gearbox 1500hrs raw water cooled and very happy with it since I bought boat last year. Did three 24hr trips of motoring bringing boat back from France to Ireland and she didn’t miss a beat. Gives a bit of steam after 2500rpm but I think this is normal enough for a gm.
 
westhinder said:
I am having exactly what you describe with my folding prop. It has got worse since I got a big clump of fishing net and ropes around my prop a few weeks ago. Since then I have noticed that after reversing and putting the gear in neutral, the prop continues to rotate.
I am expecting a mechanic aboard tomorrow. Do you think that it will be a matter of lapping the cones as you describe, or is this more serious?

Edited to add: this is on a Yanmar 3JHE, I do not know the type of gearbox.
Click to expand...

It's possible that your cones may have become "glazed" and have stopped gripping. You can check to see if your shaft is not turning evenly and that will be a clue. BEWARE!! Many mechanics who aren't conversant with the engine (and actually some who should be...) look at the ridges on the cones and tell you that you need new ones. This is not so!! Gentle lapping in will cure this. Diagnosis is not cut and dried and the only true way of telling is to strip the box and force the cones together and twist by hand, If they don't lock together and grip each other, get out the lapping paste and a slow turning lathe and lap by hand. Good luck!
 
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