outdrive oil leaking

adamsel

Recruit
Joined
Sep 17, 2013
Messages
4
I have a 2008 Tahoe q7i 350 mag with b1 out drive. level has been Lowering I don't notice it while in use but while it is sitting between uses the reservoir lowers and gear oil ends up in the bilge. Thanks for the help
 

MarkSee

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Sep 10, 2010
Messages
1,172
Re: outdrive oil leaking

Welcome to IBOATS.

Looks like it could be the classic case of the front yoke seal failing and getting into the bilge.
But before pulling the driving and seeing gear oil in the bellows, trace back from the bottle to the transom and make sure you see no leaks there.

Happened on my B3 last year and I had to replace that seal.

Mark
 

adamsel

Recruit
Joined
Sep 17, 2013
Messages
4
Re: outdrive oil leaking

Welcome to IBOATS.

Looks like it could be the classic case of the front yoke seal failing and getting into the bilge.
But before pulling the driving and seeing gear oil in the bellows, trace back from the bottle to the transom and make sure you see no leaks there.

Happened on my B3 last year and I had to replace that seal.

Mark
I tried getting back in there, couldn't get all the way back but could see oil right below hose but couldn't get my hand back there to find end of hose. Where will the oil be coming from if the seal is leaking.
 

alldodge

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Mar 8, 2009
Messages
43,740
Re: outdrive oil leaking

As Mark See mentioned it could be the outdrive bottle hose, mine started leaking also. Taking a page from Bondo use a mirror or camera, they can fit were your head cannot.
 

MarkSee

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Messages
1,172
Re: outdrive oil leaking

I tried getting back in there, couldn't get all the way back but could see oil right below hose but couldn't get my hand back there to find end of hose. Where will the oil be coming from if the seal is leaking.

I know what you mean. For me to check the hose behind the engine on the transom I had to lay across the top of the engine banging my head on the engine hatch, scraping my arms on various things and using a flashlight and mirrors just to verify the fitting nor hose was leaking.

The fluid will be coming from the yoke that goes into the engine coupler; you may or may not be able to actually see it leaking.

Do you do your own maintenance as far as pulling the drive off which will show right away if you see gear lube in the ujoint bellows?

Look at this link on page 3a-8 for an idea of what the seal is and other pages in that section to replace it. A couple special tools needed if you do it yourself.
Boatinfo - Mercruiser Service Manual nr. 28 - 1999-2006 - Bravo One, Two, Three & XZ/XR Sterndrives

Mark
 

adamsel

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Joined
Sep 17, 2013
Messages
4
Re: outdrive oil leaking

Is it safe to operate as long as I keep the reservoir full or is it all stop until the problem is resolved. I would prefer not to cause any damage to outdrive
 

MarkSee

Lieutenant Junior Grade
Joined
Sep 10, 2010
Messages
1,172
Re: outdrive oil leaking

Even keeping the reservoir full won't keep oil from being slung around in the bellows or continue to dump in to the bilge but, depending on how bad the leak, is the way to keep from destroying the drive. That does not mean you should put off getting it checked out and repaired in case the leak were to quickly worsen and empty the bottle.

Even in my case, I noticed the level in the bottle going down a little bit and topped off the bottle thinking maybe it was just an air pocket that filled from when I did the last lube change. Then after the next time I noticed it had gone down a little also and topped it off again. Then one day I noticed lube on the ground beneath the drain plug hole and the bottle was down even further that alerted me to check the bilge and found the lube in there.

Now I started looking for a leak in the bottle/hose going back to the transom and found nothing. At this point I cleaned what I could in the bilge and on the ground then topped off the bottle and did not start the boat. Came back a few days later and sure enough, lube on the ground and in the bilge. (Note that a pro would have not needed to do that last step as they would have already known what it was but I did not know any better at the time and wanted to verify it was losing lube just by sitting there without running).

Got help from my mates here at IBOATS on what needed to be done (pressure test, seals, tools) and clarifying what I was reading in the manual and now no more leak.

Mark
 
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