BayField 25

[KivaSimo]

In 2018 we purchased a BayField 25, 402 production number built in 1979.
It came with a Yanmar YSM8R engine. The boat has been well maintained since its production. The gentleman we purchased from was an excellent diesel mechanic. He is no longer available, I am on quick learning curve. Sorry for the long introduction. Late last year black oil began appearing in the bilge but not under the engine. I would appreciate any insight given.

[thomm225]

What year is the engine?

[JoeRobertJr]

Hi, KivaSimo, and to the forum!

I think your question is how to identify the source of the oil leak from the engine? How difficult is access to the underside of your engine? Can you clean it? Can you place some oil absorption pads or even just paper towels under it to help roughly locate the source of the leak? Likely sources are the seals on the crankshaft, a loose oil filter, loose oil drain plug, oil pan gasket, head gasket.