1997 90 hp BF90 Oil Leak and Water Itrusion

"I have an oil leak that increases when the engine is tilted up. When I drained the oil to trouble shoot I found significant water intrusion into the oil pan. When I had the engine tilted up to remove the gear and extension cases, oil was coming from the area that the vertical shaft goes into. I think it may be one, or a combination of the following: the mount case water seal, mount case gasket, oil pan gasket, or the head gasket. Oil was only present along the path of the vertical shaft and the exhaust tube was dry. I have all gaskets on hand but don’t want to go for the head gasket unless I have to. Any ideas?"

"Take a look at my posting for

"Take a look at my posting for "Oil leak Honda 130". The 90 and 130 may be very similar.I have my 130 apart for the same problem. I discovered that the leak was around the shift shaft "A" that your long shift rod goes into. There are 2 seals around shift shaft A, one to keep water out, the other to keep oil in. The only way I know to replace these seals is a complete removal of the power head and the engine mounting case where the shift shafts are located. The seals on my engine were completly corroded away. I'm now ready to order all new seals, gaskets, etc. and start reassembly.
Dick"

I have mine apart now too. the

I have mine apart now too. the mount case water seals look worn. Replace them all and cross fingers.