Oil Leak

[PeeWee]

I am underway in a cat . I have two engines , no wind, but getting along ok on one engine.
I have lost all oil in one engine , is now in bildge.
Yanmar 3gm30,s .
To hot to get down and have a look at present.
Appears to be coming from pully end .
Any idea what may be leaking here.
Main shaft seal looks ok .
Hoping just oil filter , as did change recently , but again , frm what i can see , it appears to be coming out slightly lower.
Any advice appreciated , never nice when underway .

[jt11791]

I think that motor has an external high pressure oil line. The oil line is steel and has been known to rust through.

[sailorchic34]

A oil seal would seep and take a long time to loose even a pint of oil. If the oil filter is tight and not leaking, the external steel oil line behind it could be the primary cause. If it looks lumpy/rusty it probably has a pinhole leak in it.


Yanmar has a copper line replacement. Or if you find 3/32" copper tubing, you can drill out the banjo bolt (with 3/32" drill bit) and rear 3 way block and solder in a new oil line. Solder, do not braze.



I rerouted mine to above and around the starter.



If the oil line is good, then check that the crankcase breather (left rear of valve cover) is not clogged.

[PeeWee]

Done a bit of research on here and will check out the line, once i anchor up later.
Thanks.

[PeeWee]

just climbed into engine bay , and does not look like ex oil line.
Appears more at the opposite end of engine under oil filter somewhere.
??

[flyingfin]

Did the rusty spot on the bottom of the oil pan finally blow out? Run your hand around the entire bottom of the oil pan. And for those of you without a problem, put on a nitrile glove, grab a handful of wheel bearing grease and give your oil pan a good massage

[sailorchic34]

Originally Posted by PeeWee

just climbed into engine bay , and does not look like ex oil line.
Appears more at the opposite end of engine under oil filter somewhere.
??

Odds are the oil filter is loose. The vibration of the engine will sometimes loosen one. I've found one of mine barely hand tight. but that could have been due to someone not having enough umph to tighten it enough.



Note the part of the external oil line that leaks generally is behind the oil filter and right before the starter. It tends to rust out 2" from the baanjo bolt / near the starter. The oil line runs behind the starter to the rear and around to under the exhaust manifold.

[PeeWee]

I will check lines again , but believe with my saildrives , my engines are facing backwards with sail drive towards the bow.
There is no oil in the area of the ex line .
Took pic but cant seem to post
ps, thought i had apretty good hold of filter , but did only do by hand