Oil Leak. Silly Question

Have had an oil leak on my 1989 starboard 5.7l Merc. that nobody can find. No obvious visable signs of where it is coming from. Ends up in bilge. Had people look at with mirrors and all and nobody can tell where. I always thought it only did it when running, but I just went out to the marina to start to get it ready to go in and noticed that there is more in the bilge than when put away. They are about to pull the motor to try to tell where it is coming from, but as I make the ride home I can't help but think that maybe it is leaking from the drain plug. Question is... Does this motor have a conventional automotive drain plug? I always suck out of the dipstick and never paid attention if it has one, and other than that, where could it be leaking from at rest?

Re: Oil Leak. Silly Question

It wouldnt hurt to get a dye kit first. aput die in the oil and use the supplied light after running you can determine the origine of the leak faster.

Re: Oil Leak. Silly Question

Re: Oil Leak. Silly Question

I believe most do have a traditional drain plug. I would not let them pull the engine yet. Spend some time cleaning it up real good, the engine and bilge. Keep a close I on it, use a mirror and your finger and feel around until you find that leak.

Re: Oil Leak. Silly Question

Is it inboard or I/O?

Re: Oil Leak. Silly Question

Straight inboard.

Re: Oil Leak. Silly Question

Any signs of rust on the oil pan? The dye kit is a good idea..