Hi...I have a 1987 Hunter 34' sailboat with a Yanmar 3GM30F engine in her. The last time I took the boat out, I noticed about 1/2 Quart of oil in the pan below the engine when I returned. I promptly checked the oil and it was low. It seems like it is dripping from the rear starboard corner of the oil pan. Does this mean it is a main seal on the engine?
Oil Leak
- Thread starter Randy Miller
- Start date
If, as you say, it’s leaking from the “corner of the pan”, it’s likely the pan gasket.
DO NOT look for the most difficult (aka $$$) thing on the engine to repair at the onset. Look for the easiest and eliminate each item as you go along. There are MANY sources of possible oil leakage. A pressurized crankcase is always a suspect. 1/2 a quart oil loss is one huge leak and will be easy to find. How many operating hours on the engine.
My first suggestion would be to scrupulously clean off all oil from the rear of the engine top to bottom. Place clean newspaper under the engine. Next, start the engine and run for 1 - 2 minutes, shut down and look for a possible source of the leak. Keep repeating this with longer running running periods until the leak reveals itself. It may not start to leak until the oil is hot.
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Could be the oil pan or it could be from somewhere above. Wipe everything clean and then use a UV dye kit to trace the leak.