Pressurizing Outdrive

[Maxum88]

I'm trying to pinpoint a leak in my outdrive and was wondering if I can pressurize the lower unit while removed from the upper unit, or if it has to be together? With them separated and plugging up the oil passage, I'm leaking out of the oil carrier assembly (the water pump is removed). Can I do it this way? I downloaded the 673 page #14 service manual to ensure everything goes back properly, but I didn't find any procedures for narrowing down a leak once detected while the outdrive is assembled. Or do I just do all the seals and recheck?

Thanks in advance for your help! The price at the shop for an upper and lower seal job is starting at $400, just trying to save some cash but do it right!!

1995 Mercruiser Alpha One Gen II
1995 3.0L Mercruiser LX

-Tim

 

[cecho]

Re: Pressurizing Outdrive

You can test the drive when it's separated. Once you plug up the oil passage it should be able to hold pressure up to 12 PSI and vacuum down to 5 HG. Use soapy water in a spray bottle to find the leak.

 

[achris]

Re: Pressurizing Outdrive

...With them separated and plugging up the oil passage, I'm leaking out of the oil carrier assembly (the water pump is removed). ...

Hi Tim,

You found your leak. Get a complete seal and water pump kit (-817275K05), replace the seal carrier under the water pump and retest it...

 

[Maxum88]

Re: Pressurizing Outdrive

Thanks guys!!! I had oil leaking from the water intake slots. Is the same for the upper unit? Can I plug up the hole and do the same through the vent?

 

[Don S]

Re: Pressurizing Outdrive

Thanks guys!!! I had oil leaking from the water intake slots. Is the same for the upper unit? Can I plug up the hole and do the same through the vent?

Yes

 

[Maxum88]

Re: Pressurizing Outdrive

That's what I was afraid of...the upper unit doesn't hold any pressure with the oil passage hole plugged. Seems to be coming from when the drive shaft enters the upper unit. Any special tools required to do this seal? I didn't see much in the manual for the upper unit seals.

 

[MarkSee]

Re: Pressurizing Outdrive

Seems to be coming from when the drive shaft enters the upper unit. Any special tools required to do this seal? I didn't see much in the manual for the upper unit seals.

SM #14 page 3a-4, item #18 is a seal that the drive shaft comes through. Is that where you are saying it's leaking out of?

If so, you'll need the tool to remove the retainer nut(item 14) and also a torque/socket wrench and inch-pound torque gauge to set the pre-load when re-installing. Also need to check the yoke for any grooving once you get it apart.

There is another thread going on right now where a guy is asking a similar thing; might want to check that out.

Also Achris has a video where he shows about setting the rolling torque.

Mark

 

[Maxum88]

Re: Pressurizing Outdrive

Thanks Mark! It's hard to tell with everything assembled, but I think that seal is a good place to start.

 

[achris]

Re: Pressurizing Outdrive

Thanks Mark! It's hard to tell with everything assembled, but I think that seal is a good place to start.

95% of top box leaks are that seal... Here's the link to my video.

5 Drive gear preload - YouTube