View Full Version : 3GM30FYEU Oil sump leak

01-23-2010, 04:46 PM
"I have a persistent leak which looks like its coming from the oil sump packing. My engine has about 1000 hrs. I purchased a new packing, removed all 21 bolts and expected the sump to drop. It won't budge. How do you get it off???"

01-23-2010, 06:08 PM
When you refer to the oil sump packing are you meaning the oil pan and gasket on the bottom of the engine?
I have a similar problem and the leak is at the rear of the engine on the left.
I will be interested in any reponses to your post.
Capt Steve

01-23-2010, 06:46 PM
Yes that is what I am referring to.

05-11-2010, 01:55 PM
I have 2 3gm30fyeu in my catamaran. At about 1500 hours one started to leak oil at rear of engine. Turned out to be rear crankshaft seal. At about 1700 hours I had it replaced. The machanic just pulled the old seal out and "tapped" a new one in. AT about 1900 hours the other engine started to leak and then at about 2000 the first one started to leak again. I keep both engines at almost the same engine hours. Last fall at about 2500 hours I had the second engine's seal replaced. This time the mechanic (different) removed the carrier plate at the rear of the engine that holds the rear crankshft bearing and the seal to replace the seal. Bottom half of the crankshaft bearing also severely worn. Had engine torn down and front crankshaft seal lower half severely worn. All other bearings, rings, cylinder walls perfect condition. Mechanic and Yanmar blamed me for problem, idle too much clogged mixing elbow, etc - all of which not true! And since over 2 years old, my problem. Anyway, clean engine well with brake parts cleaner and use a mirror and flashlite to look under rear of engine. Oil was coming out of join of flywheel housing and the plate on rear of engine.
I really hope that this is not your problem - $3500 to have engine removed, rebuilt, and reinstalled.
Capt Dave