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Drive Gear Oil in Bilge.

1754 Views 15 Replies 6 Participants Last post by  powerplay5.7
Does anyone out there have any idea what would cause outdrive gear oil to end up in the bilge?

Ive got a 87'alpha 1, and after a run this weekend I noticed my bilge was full of oil. First I thought it was motor oil, but after closer inspection found it to be gear oil, so I pulled the drive drain, and vent and only got 2oz of lube out of it. Any Ideas.......
THANKS!!!!
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On a Bravo drive there is a seal behind the u-joints. I'm sure an Alpha has one as well. When it goes bad it will dump the drive oil into your bellow and then into the bilge.
Front Univeral seal as described above.
Thank you guys

Yes sir its the front yoke seal, was going to try and repair it my self, but found out there are some special tools required, and if not done correctly you can end up causing more damage than there was originally. So its going in tomorow for a whole drive service, water pump,bearings if needed, boots, shift fork, boots, bellows, and gimble. Nobody ever said boating was cheap.... THANKS for all your help guys much appreciated!
One more thing

I was also told this is rare seal to go bad, causes could be either dry rott, which i assume is my case with the boat bieng an 87'. But the other cause would b a missalinged drive wearing one part of the seal more that the others, just food for thought. THANKS again.
Don't see how an engine/drive misalignment can cause a seal to wear out. You'd have to ruin the front bearing first to effect the seal.
When this seal goes bad will the drive oil leak down when sitiing or only when running?
I had to top off my drive fluid a couple times last season and after the winter the tank resivoir was empty and the bilge was full :dead: , I assumed it was leaking from the tank or hose but cant find a leak anywhere. Didnt think of the seal.
Its my understanding that if your drive, and engine alingment is off, the yoke will be off-center in the bearing, as well as the seal. I would have to believe that yes this would wear out the bearing too, but a rubber seal is going to wear out much faster that a sealed bearing. Its very simiilar to pinion angle on a rear differental on a truck.
Mine only leaked when running. The gear oil was following the yoke shaft up, and with no seal there to stop it, it filled the bellows up and the next stop was my bilge. what a mess it was too. took three bottles of degreaser to get it clean.
The alignment is mostly for engine, coupler and gimbal bearing. The yoke is bolted to the bearings. Technically the only time the drive is in alignment is when it is at neutral trim and in straight position. Thats why there are 2 U-joints on input shaft. Yoke seals go bad mostly from having had water in bellows or just age. I wouldn't call it rare we see more than 10or so a year. If they are saying your alignment is that bad you need to look at the splines on your input shaft and the splines in the coupler for wear thats what a bad alignment will cause.
Thanks for the info curtis, all this drive stuff is new to me so im just learning. You sound like you have some experiance with this stuff. I was just sayn what I was told, this is part of the reason why I prefer to do all my own work on anything I own, so I know im not getting screwed around by some jerk store that just wants my dollars. Sounds like you have replaced these seals before, is it a job for someone who knows what there are doing or can it be done by a first timer? I work on cars for a living so im really not scared of doing it I just dont want to get in over my head and keep the boat off the water any longer than its already going to be.
It's not a real hard job. If you turn wrenches and can read a manual w/ right tools anyone can do it. The hardest part is setting the preload on the the bearings. Which takes multiple attempts on tightening the bolt to the yoke and doing rolling torque to set preload. Proper tools and patience is all you need if your a tech you already know that.
You can call me at the shop and I'll talk to you about it. It's busy so you might have to leave message. Thanks, Steve
Thanks steve for your kind help, I swear there are no people on earth as friendly as boaters. I will give you a shout either today or tomorow. It sounds alot like how you would set up a rear end. the only thing i need to know is what special tools are required, but ill just give you a shout. Thanks again!! btw my mane is mike.
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