outdrive oil leaking inside boat. reservoir part number? 2008 Mercruiser 5.0 Alpha one

mnypitboat

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outdrive oil leaking inside boat. reservoir part number? 2008 Mercruiser 5.0 Alpha one

OK this is driving me nuts. I cant find a leak anywhere, but a 30 minute trip on plane and the reservoir is empty and its all in the bottom of the boat. I replaced the cap thinking it had lost its pressure, but its still leaking. There is no visible leaks at idle or off. I pulled off the reservoir and filled it with fluid and put it in a bench vice and let it sit a week and it did not leak. The line going all the way back seems to be fine.

The only thing I can find is a bit of oil underneath the reservoir, but I am not sure if that is from me missing the hole when refilling it.

So any ideas? If I cant find anything else I will just buy a reservoir I guess. Only one problem with that. I cant find my reservoir part number anywhere. It looks like the rectangular one that is held in by what looks like a rubberband, but mine is mounted with a bracket instead and has a hose pressed onto it and goes back to a quick disconnect plastic fitting behind the engine. Any idea on a part number?
 
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Bt Doctur

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without an external leak with the hose or connections, then pull the drive and check the bellows for gear oil
 

mnypitboat

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without an external leak with the hose or connections, then pull the drive and check the bellows for gear oil

Would that push it up into the bottom of the hull? Not looking forward to pulling that out again.
 

Bt Doctur

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it comes out of the front seal of the drive where the shaft enters the upper unit
 

mnypitboat

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I cleaned the reservoir off, gonna fill it with fluid and see what happens. If it stays clean but fills the hull again, then I may just bring it in to be looked at. Is there no way to check that without pulling the drive?
 

Bondo

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Is there no way to check that without pulling the drive?

Nope,... It's only 6 nuts, 'n a couple of clips,... Pull it off, 'n get it fixed,....

The repair co$t$ will continue to rise, the longer ya run it,...
 

Fun Times

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Need your engine serial numbers to find the correct part numbers.
 

mnypitboat

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Recently we pulled the bottom of the drive off to have a new skeg welded on. Is there anything that could have happened in there to cause this? Its not leaking into the water, just in the hull, so I dont think so, but what do the experts say?

Its definitely not the reservoir. It is perfectly dry. It is leaking a lot though, a quick 45 minute ride, mixed on plane and idle zones, and I had to fill it up twice.
 

mnypitboat

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OK its off, AGAIN. I take it the upper bellow is not supposed to be full of gear oil? This is the 4th time in the last year that its been off.

So what does it take to replace those seals? I assume it requires special Mercruiser tools.

Since I do NOT want to pull this off again any time soon, is there anything else I should do while its off?
 

Bondo

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I take it the upper bellow is not supposed to be full of gear oil?

Ayuh,.... It should be full of Air, 'n maybe some purged grease from the gimbel bearin',.....

Once ya get the oil cleaned up, how do the bellows look,..?? dry-checkin',..?? cracks,..?? how old are they,..??
How 'bout the lower shift cable,..?? How old is it,..?? ditto the sender, 'n trim limit,....
 

mnypitboat

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We just did the bellows in January, and they are brand new. Gimbal bearing was replaced very soon after that. My concern now is that all that gear oil has been passing through the gimbal bearing. Is there a way to grease it? Or will it be OK?

Not sure about the rest. I suppose if they arent too expensive I will just replace them.

The good news is that the oil was perfectly clean. No water intrusion, and the lower magnetic plug was perfectly clean of any particles.
 

mnypitboat

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I brought the outdrive to a shop. The guy said $350 to replace the seal and fill with fluid. Then called me yesterday and said it needed a shaft to the tune of $675. OK now I am at the point where I can almost replace it with a rebuilt unit.

Does this sound right? Now he wont even put it back together so I can put it back on and trade the boat in. He says he wont do anything unless I spend all that money. We were considering buying another boat, and the big Orlando boat show is this weekend, so I figured I could use that $1000 to put down on something else.

How hard is it to do that stupid seal and can I do it myself with a couple tools off ebay or something? What do I really need to do this job? If I can rebuild a T56 or a 4L80E transmission I am sure I can handle this with the right tools.

This is why I hate shops.
 
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