Alpha One upper shift shaft seal....

KewlBird

Petty Officer 1st Class
Joined
Oct 6, 2007
Messages
247
Well guys I am replacing my bellows, and trim senders..... I was inspecting things and noticed that the upper shift shaft seal was dry and cracked, so I decided to get a new one..... I removed the old old one but behind it was another one! It looked the same and was also in bad shape...I checked the manual and from what I see there is only one seal there, Should I get another one and stack them? or is one sufficient?
Just to explain the location of this seal....Upper shift shaft in the bellhousing.....The seal sits in a brass (?) guide/bearing....There are two of these bearings...This is the top one...bottom one doesn't use a seal. The shift shaft goes in from the bottom ....BTW, this is on a 1990 Alpha one gen I....
Thanks!
 

JustJason

Vice Admiral
Joined
Aug 27, 2007
Messages
5,321
Re: Alpha One upper shift shaft seal....

If its what i'm thinking your describing, then there is a seal, a bushing and thats it. Theres 2 different sizes, 5/16ths and 5/8ths... so you need to know which one you have.
 

Apollo75

Petty Officer 1st Class
Joined
Sep 2, 2009
Messages
272
Re: Alpha One upper shift shaft seal....

Are you looking at parts #6 bushing and #7 oil seal ?

The exploded view shows two seals back to back ---- must be open to inside of the bell housing case at that point.


Good Luck


OFM
 

45Auto

Commander
Joined
May 31, 2002
Messages
2,842
Re: Alpha One upper shift shaft seal....

You probably need the upper seal upgrade for your Alpha Gen I. Makes it the same as the Alpha Gen II. It has bigger diameter dual seals that will help your lower shift cable live much longer.

Part #7561, about halfway down the page:

http://www.mercstuff.com/bellhousingstuff.htm
 

KewlBird

Petty Officer 1st Class
Joined
Oct 6, 2007
Messages
247
Re: Alpha One upper shift shaft seal....

Are you looking at parts #6 bushing and #7 oil seal ?

The exploded view shows two seals back to back ---- must be open to inside of the bell housing case at that point.


Good Luck


OFM

That's exactly what I'm looking at.....The seal goes inside that bushing...only difference mine had 2 seals inside that bushing...I'm reusing the old bushing because it wasn't readily available and mine is ok...
 

KewlBird

Petty Officer 1st Class
Joined
Oct 6, 2007
Messages
247
Re: Alpha One upper shift shaft seal....

Well, I've been searching around and I'm not coming up with anything......All that I've found is that there is one seal in there (not 2)....There is supposedly an updated bushing kit part# 18-2622 , but I can't find any info if that has two seals or not..... I plan on going ahead with the single seal....I really want to start putting this thing back together tomorrow morning....
 

Apollo75

Petty Officer 1st Class
Joined
Sep 2, 2009
Messages
272
Re: Alpha One upper shift shaft seal....

Maybe someone upgraded it to Gen II --- check this out and see if the seal and bearing kit looks like the ones you have. Probably goes by serial number like everything else.

I know the exploded view of Gen II has two seals.

http://marineengineparts.com/shopsite_sc/store/html/page259.html

Where are the marine mechanics when you need them. :p

F094774 & Below Gen I

Above Gen II Stuff

Try here --> http://www.mercstuff.com/bellhousingstuff.htm

Yeah there it is, nice new mod with two seals in a nice brass bushing :D


OFM
 

"G"

Petty Officer 2nd Class
Joined
May 2, 2009
Messages
150
Re: Alpha One upper shift shaft seal....

Shift shaft leaks were usually repaired by replacing both the bushing and the shift shaft. Even so... re sealing isn't wrong either. Just be sure the SS is not grooved at the seal and you use caution in reassembly.

Think about what you are "sealing" out/against. One seal seals out water/ dirt/sand etc. The other seals oil from leaking out. Some seals have a upper and lower seal built in. Check your replacements... If I had to chose one I'd use the seal faced to the oil and put a "slinger" over the top of the SS bushing. Frankly, I'd go with both... double caution for a muddy area.

Need I say...The bottom one goes in seal toward the skeg, the other faces up toward the engine housing. Hope that helps. ;)
 

KewlBird

Petty Officer 1st Class
Joined
Oct 6, 2007
Messages
247
Re: Alpha One upper shift shaft seal....

Maybe someone upgraded it to Gen II --- check this out and see if the seal and bearing kit looks like the ones you have. Probably goes by serial number like everything else.

I know the exploded view of Gen II has two seals.

http://marineengineparts.com/shopsite_sc/store/html/page259.html

Where are the marine mechanics when you need them. :p

F094774 & Below Gen I

Above Gen II Stuff

Try here --> http://www.mercstuff.com/bellhousingstuff.htm

Yeah there it is, nice new mod with two seals in a nice brass bushing :D


OFM

Awesome! That second link had exactly what I was looking for!
"The large diameter will extend into the exhaust cavity but will have no affect the exhaust. This upgrade kit now has 2 heavy duty seals installed compared to the one thin seal shown above."
From the looks of it the bushings must've been upgraded at one point in time.....I was able to read the part # on the second seal and it's 26-816464 which is exactly what I bought as a replacement......So I'll be adding one more seal in there.....Thanks to all the replies, that's a load off of my mind....
BTW, there was no known leaks at the shift shaft, only reason for the replacement was that the seal that was visible was dry and cracked!
 

45Auto

Commander
Joined
May 31, 2002
Messages
2,842
Re: Alpha One upper shift shaft seal....

Obviously you never read post #4 .......

:D
 

Apollo75

Petty Officer 1st Class
Joined
Sep 2, 2009
Messages
272
Re: Alpha One upper shift shaft seal....

Obviously you never read post #4 .......

:D

That will teach me to read all the posts --- I had to research that myself --- he, he. :p

Good job 45Auto :D


OFM
 
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