Merc Alpha Swivel Shaft, Bushing, Seal Info???

[Brentathon]

I'm trying to look into the details of what parts are required to replace my Merc Alpha Gen I Upper Swivel Shaft Seal, and the exploded parts list seems confusing. Does anyone have detailed knowledge of this particular job?
-Since I have no grease fitting on the top of my gimbal housing, does that mean that I have a newer style square-to-square upper swivel shaft (in lieu of square-to-spline)?
-How many bushings are there for the upper swivel shaft (on the upper part of the gimbal housing and gimbal ring)?
If I assume that I have the new square/square setup: I see one seal p/n (26-8M2005029), and two bushings p/n's (23-98356, 23-983571); are these 3 parts all used on the upper swivel shaft?
Is the nylon bushing 23-99352 used at all?

 

[stonyloam]

Re: Merc Alpha Swivel Shaft, Bushing, Seal Info???

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Is the nylon bushing 23-99352 used at all?

Yes that is the bushing for the lower swivel pin on the bottom of the ring, and should be replaced if you have it all apart.

 

[Brentathon]

Re: Merc Alpha Swivel Shaft, Bushing, Seal Info???

Oh, Ok. Thanks.
Anyone know a way that I could tell if I have the square-to-spline shaft, or the square-to-square shaft?

 

[stonyloam]

Re: Merc Alpha Swivel Shaft, Bushing, Seal Info???

-Since I have no grease fitting on the top of my gimbal housing, does that mean that I have a newer style square-to-square upper swivel shaft (in lieu of square-to-spline)?

No grease fitting is a pretty good indication, also if newer than mid 80's, but you can check the SN: From the "book"

"Transom assembly serial number 6666130 and
above.
A new square swivel shaft steering lever provides a
square connection at both the steering lever and gimbal
ring for improved durability."

 

[Brentathon]

Re: Merc Alpha Swivel Shaft, Bushing, Seal Info???

It's either a 1990 or 1991, and the sticker on the plastic flame arrestor cover had OD488479 for the transom serial number. Does that mean anything? What do the letters "OD" signify?

 

[stonyloam]

Re: Merc Alpha Swivel Shaft, Bushing, Seal Info???

It's either a 1990 or 1991, and the sticker on the plastic flame arrestor cover had OD488479 for the transom serial number. Does that mean anything? What do the letters "OD" signify?

Not sure where the SN is, but a 1990 Alpha I will have square to square.

 

[Brentathon]

Re: Merc Alpha Swivel Shaft, Bushing, Seal Info???

Ok, thanks.......that's what I've been kinda guessing, to.
And I think the fact that I have no grease fitting for the upper swivel shaft, indicates that, too, and there's a different arrangement of bushings and seals for that later design shaft, too........I think.
It appears that Alpha Gen II's use the same seal (26-8M2005029) for the upper swivel shaft, but the Gen I's use two of them (one on top, one on bottom of the lower SS bushing(23-983571))?
I just wish I could get even more details of this job, as I REALLY don't want to pay the high costs again, to replace this darn seal.
Most Alpha's I see on other boats (especially smaller boats), have their swivel shaft area well above waterline; where mine is below waterline as soon as 1 person steps aboard