Merc 90 late 80s vintage - prop seal advice

[CharlieZulu]

Lower unit oil has water in it, so time to have a look. First time I've tried. See pix.... Is this O ring all that keeps water and oil apart???

 

[Laddies]

Re: Merc 90 late 80s vintage - prop seal advice

There are 2 seals on the prop shaft, 2 under the water pump and 1 on the shift shaft. the last 3 require the unit to be remove from the mid section to be changed.

 

[CharlieZulu]

Re: Merc 90 late 80s vintage - prop seal advice

You can see the O ring in my pic..... Where is the 2nd seal located? Maybe mine is missing??

 

[Laddies]

Re: Merc 90 late 80s vintage - prop seal advice

Pull the prop shaft out of the carrier and you will see the 2 seals 1 goes in and the other out.

 

[CharlieZulu]

Re: Merc 90 late 80s vintage - prop seal advice

I have the shaft out..... where are these mysterious seals?? See pic.

 

[Laddies]

Re: Merc 90 late 80s vintage - prop seal advice

That would be items 66 and 67 on this link if you can see them.
http://www.mercruiserparts.com/Show...8&bnbr=23&bdesc=GEAR+HOUSING(PROPELLER+SHAFT)

 

[CharlieZulu]

Re: Merc 90 late 80s vintage - prop seal advice

Thanks folks, so far so goodthis is my first time. So how do I get all the guts out of the Carrier Assembly I can see the messed up seal:

 

[Laddies]

Re: Merc 90 late 80s vintage - prop seal advice

Reach thru the prop shaft bearing with a long punch and drive the seals out, by tapping on one side and then the other to keep the seals from binding

 

[Maxz695]

Re: Merc 90 late 80s vintage - prop seal advice

on the front of the carrier

 

[Chris1956]

Re: Merc 90 late 80s vintage - prop seal advice

Charlie, There are also seals in the base of the waterpump for the driveshaft and around the shif shaft. These are a lot easier to change than the propshaft seals.

 

[Maxz695]

Re: Merc 90 late 80s vintage - prop seal advice

View attachment 171828 water pump base O ring

 

[CharlieZulu]

Re: Merc 90 late 80s vintage - prop seal advice

Holy cow I am finding this tough....I put a large flatwasher down in there and have been pounding on it with a large punch and nothing seems to be moving. are all the components inside the carrier removeable? Am I whacking on the right thing?




The other end:

 

[CharlieZulu]

Re: Merc 90 late 80s vintage - prop seal advice

In other words, can the two rubber seals be replaced without tearing all the guts out?