Yanmar oil leak

gnutkase

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Actually it is a bit more than an oil leak. First visit to Moody 422 since February. Went to pump out bilges to find they not only had water in them but about 4 inches of thick black engine oil. Doesn't appear to be any oil left in engine at all. pipes all seem to be connected. Assume the plug at bottom of engine has disintegrated?

Husband was engineer but unfortunately died in May, so I am completely clueless as to what may have happened between Feb and now.
 
Condolences for your sad loss.

It's very surprising to hear that an engine has lost all it's oil in such circumstances but if there is no oil showing on the dipstick then it appears that something low down in the oil circulation system must have given way. The sump plug is a possibility but it seems unlikely. The only way to be sure of probably to put more oil in and use an endoscope or mirror or phone camera to have a good look around, behind and under the engine.

Richard
 
It would help to know which model Yanmar it is. Most don't have sump plugs.
Some Yanmars do have external oil lines though and these can rust through.
An sump without a sump-plug can only empty when running via a substantial leak somewhere.

The easiest way to find the leak is probably to wash out the engine bay as best you can so any new leak will be immediately apparent, (even spread newspaper under the engine if you can) refill the engine with oil andf run it briefly before stopping to observing where oil is leaking from.
A leak big enough to empty the sump should be readily apparent.
Do you have any mechanically minded yachtie friends who might help?
 
Welcome and sorry to read about your husband.

Do you really think it's necessary for you to try to find the leak?

How does that help when you inevitably call an engineer?

Yes, wash the engine bay and bilge to prepare for the investigation but what are you going to do if you find the source?

Certainly not fix it yourself.
 
Its a JH Series engine fitted in Jolly Harbour Antigua around the late 1990s.
Don't know those, apparently the YMs and GMs get through rear crank seals at a pace, mine had oil running out of there for a while. If it is that then it'll be leaking from the vents in the bell housing that cover the flywheel between engine and gearbox.

I don't think it has a sump plug so the most likely thing to break at the bottom of the engine would be the dipstick.

You could always pour a bit more in and see where it drips.

A broken dipstick or oil cooler piping is easily fixable by a normal person.
 
Don't know those, apparently the YMs and GMs get through rear crank seals at a pace, mine had oil running out of there for a while. If it is that then it'll be leaking from the vents in the bell housing that cover the flywheel between engine and gearbox.

I don't think it has a sump plug so the most likely thing to break at the bottom of the engine would be the dipstick.

You could always pour a bit more in and see where it drips.

A broken dipstick or oil cooler piping is easily fixable by a normal person.
The dipstick isn't broken - it's just very clean and untroubled by oil! I'm glad it hasn't got a sump plug as I can't imagine how you would check it as the engine sits on the hull.

My husband did have the gearbox out the year before last, but I'm pretty sure there hasn't been a leak until now. I have a friendly mechanic (diesel but not marine diesel) who will come and have a look for me.

Just have to clean out all the bilges now - not looking forward to that!

Thanks for your suggestions.
 
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