Oil in the gimble bellow

magregor22

Seaman Apprentice
Joined
Jun 29, 2002
Messages
41
Good day folks. I have a 1979 470 Merc with a pre-alpha drive. Earlier this summer I found oil in the U-joint bellows mixed with a small amount of water. i presumed it was coming from the upper drive seal. When I went to reseal the drive i broke the bolts to the upper water pocket cover and ended up buying a whole different used outdrive. I removed this outdrive the other day and noticed once again I have oil in the U-joint bellows. My question is, could this oil be coming from the rear crankshaft seal? or is it definitely coming from the outdrive?
 

Haut Medoc

Supreme Mariner
Joined
Jun 29, 2004
Messages
10,645
Re: Oil in the gimble bellow

Is it engine oil or gear lube? My bet is gear lube .....Pull the drive, drain it & pressure test it....Should hold 15# or so all day long....JK
 

tootoot

Petty Officer 2nd Class
Joined
Sep 11, 2005
Messages
132
Re: Oil in the gimble bellow

Could it be grease liquifying from the gimbal bearing heating up. Couldnt be rear engine seal because it is behind the coupler which is behind the flywheel.
 

tootoot

Petty Officer 2nd Class
Joined
Sep 11, 2005
Messages
132
Re: Oil in the gimble bellow

J.kopek, I have a question about the outdrive pressure test, my 888 has a vent to exaust excess pressure. It leaks out from a small hole on the bottom of the lower unit when sitting in the hot sun. Will this effect my pressure test?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,082
Re: Oil in the gimble bellow

It leaks out from a small hole on the bottom of the lower unit when sitting in the hot sun. Will this effect my pressure test?
Ayuh,........ That'll affect the test all right,............<br /><br />It Ain't Supposed to Do That....................... :(
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Oil in the gimble bellow

The reason you get oil in the bellows, is because you are getting water in the bellows also. Then the input shaft gets rusty, causes the seal to leak, water gets into the drive and turns milky. Then it gets pushed back out into the leaky drive bellows with the rust and muck from the ujoints and gimbal bearing and you have a brown oily muck in your bellows.<br />You need new bellows, gimbal bearing, ujoints, front seal in the drive, and possibly the yoke that the seal rides on.
 
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