oil in bilge, pressure in Intermediate 85 OMC stringer

[Marshall Dylan]

Hello all, I'm another newby to the forum. Lots of great info here and it has already helped me a great deal.
I recently bought a 1985 winner boat 19' with a 5.0L OMC stringer I/O unit. It is running great and the only problem I have so far is there is some gear oil coming out of the bilge when I park it. I was checking the fluid levels and they were all good so I'm not sure where the gear oil in the bilge is coming from.
I'm guessing the Intermediate unit, and when I pulled the top oil plug (large one just left of center) it was under a lot of pressure and oil cap and oil spurted out of it when I loosened it. Is that normal? I drained all the oil out of this unit and washed the bilge out so I'll check tomorrow and see if there is any oil coming out of the bilge.
I also have a water leak in the tilt gear box (small gear box on the left side of the I/O) as there was some milky oil in this. I wasn't sure if I should worry about this too much or not. Doesn't seem like there is too much demand on that gear box.
Any help and/or ideas is greatly appreciated.

 

[havasuboatman]

Re: oil in bilge, pressure in Intermediate 85 OMC stringer

Is your oil milky? Water in a drive will cause excess pressure as it heats up. If your seals are warn, weak, or cracked, the extra pressure will force oil thru them. The convienient thing about oil is you can usually follow it's path back to the leak.
let the boat sit for a day, then pull the bottom most oil plug. If you're getting water into the drive, you will get a little bit of water out of that plug. But you have to let the drive sit so the swater can start to seperate.

 

[Marshall Dylan]

Re: oil in bilge, pressure in Intermediate 85 OMC stringer

I checked all four oil cavities.
The upper and lower drive unit look good.
The tilt drive gear case was milky, and
the intermediate unit where the pressure was built up the oil looked good.

Will the oil in this intermediate unit heat up and build pressure? I dont know if there is any cooling this section. From reading in the forums, it sounds like the purpose of this oil is to lube the drive shaft, does that sound correct? Could this be as easy as just being over filled?

Thanks for the help.

 

[Marshall Dylan]

Re: oil in bilge, pressure in Intermediate 85 OMC stringer

Update, I drained the intermediate section that had the pressure built up yesterday, and this morning there was no oil leaking out of the bilge.

 

[WizeOne]

Re: oil in bilge, pressure in Intermediate 85 OMC stringer

Update, I drained the intermediate section that had the pressure built up yesterday, and this morning there was no oil leaking out of the bilge.

Seems that oil would have to be leaking out of the forward drive shaft seal if you don't see any coming out the rear seal, behind the ball gear. You can't overfill that as you pretty much fill it to the top of fill hole. There is really nothing there to pressurize that cavity unless maybe the double bearing assy is worn and heating up.