Motor oil in the outdrive?

[jayhanig]

We had to pull the engine out today to make some deck repairs and when the outdrive was being dropped, we found what appeared to be motor oil in the part of the outdrive that remains on the transom (I think it is where the U-joint is). I checked the dipstick on the engine and the quantity appears to be normal and no obvious water in the oil.

So where did this oil come from?

120 HP GM Mercruiser/Alpha One

 

[Bt Doctur]

Re: Motor oil in the outdrive?

more than likely it is gear oil from a leaking upper seal in the drive

 

[achris]

Re: Motor oil in the outdrive?

Normal gear oil looks like a slightly thicker engine oil. The recommended oil for stern drive units is now Quicksilver High Performance Gear Lube. It's blue in colour. As BT said, oil in the bellows can only come from a leaking yoke seal on the drive. Simple job to replace, if you have 1 Merc special tool and a torque wrench. And the factory manual.

What year (or serial numbers) are the engine and drive (not the boat year, it could easily be different....)

Chris........

 

[ziggy]

Re: Motor oil in the outdrive?

if ya use the old brown gear lub, that would be my suspicion too. ft. seal leak. pressure test will confirm.
fwiw. i had similar issue this last fall when i pulled my drive too. no real consensus as to what it was from. i don't use any brown liquids in my drive (i use the green mercruiser gear lub). short of 2-4-c. i didn't get the feeling that others that that it was 2-4-c breaking down. and i grease and lub my drive liberally w/new grease and lubs yearly. i did pressure test my drive prior to disassembly for impeller replacement. it held.
hope ya find an answer to your question.

 

[jayhanig]

Re: Motor oil in the outdrive?

1985.

 

[dubs283]

Re: Motor oil in the outdrive?

i don't use any brown liquids in my drive (i use the green mercruiser gear lub).

the excess grease slung from the u-joints and gimbal bearing mix with any lube in the bellows and cause it to become a dark brown or black color

 

[Bondo]

Re: Motor oil in the outdrive?

We had to pull the engine out today to make some deck repairs and when the outdrive was being dropped, we found what appeared to be motor oil in the part of the outdrive that remains on the transom (I think it is where the U-joint is). I checked the dipstick on the engine and the quantity appears to be normal and no obvious water in the oil.

So where did this oil come from?

120 HP GM Mercruiser/Alpha One

Ayuh,... Odds are, from the Drive....

 

[achris]

Re: Motor oil in the outdrive?

1985.

Drive service manual -> http://www.4shared.com/document/zz_5pj9o/Service_Manual_06.html
Engine service manual -> http://www.4shared.com/document/hh5Z9V47/Service_Manual_10.html