Alpha 1 Gen 2 Upper Yoke Seal Replacement and ?'s

StevNimrod

Petty Officer 1st Class
Joined
Dec 13, 2008
Messages
343
I have an Alpha 1 Gen 2 (Serial number is OF2..... - I forget the rest and left my manuals on the boat) and there is drive oil in my u-joint bellow. I gather from reading that this is likely caused by a faulty Upper Gear End Yoke Seal.

Other than the wrench to take off the retainer near the yoke, are there any other special parts needed? Is this something a DIY-er can tackle?

One local mechanic told me that replacing the seal means the whole upper must be reshimmed; another mechanic told me that as long as everything is carefully put back where it came from, no reshimming is required and it's a pretty straightforward task.

While I'm on the subject, I'm planning on replacing the bellows as a preventative maintenance deal. There is no sign of water ingress into the U-Joint bellow so should I leave the gimbal bearing alone, or replace it while I'm in there? It turns freely all the way around and there are no rough spots when I gave it two fingers and a twist.

Lastly, does anyone use PerfectSeal when mating the upper unit to the lower unit? I think I did when I changed the impeller over the off-season and am wondering if using sealant may cause problems. The drive is off so I can easily redo the mating procedure.
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,344
Re: Alpha 1 Gen 2 Upper Yoke Seal Replacement

Re: Alpha 1 Gen 2 Upper Yoke Seal Replacement

The seal can be replaced with out having to shim the gearset.The biggest item is establishing the proper "rolling torque" when assembling and tightening the shaft nut.Go too far and you need to loosen the bearing package and try it again.If you had the old gear set ,all you do is just torque the nut down and your done.The new gears use the rolling torque setup, couple of ways to check are a "in/lbs" torque wrench or some cord wrapped around the bearing package and a fish scale.Adjust it wrong ,and it costs you a upper gearset.
 

StevNimrod

Petty Officer 1st Class
Joined
Dec 13, 2008
Messages
343
Re: Alpha 1 Gen 2 Upper Yoke Seal Replacement

Re: Alpha 1 Gen 2 Upper Yoke Seal Replacement

The seal can be replaced with out having to shim the gearset.The biggest item is establishing the proper "rolling torque" when assembling and tightening the shaft nut.Go too far and you need to loosen the bearing package and try it again.If you had the old gear set ,all you do is just torque the nut down and your done.The new gears use the rolling torque setup, couple of ways to check are a "in/lbs" torque wrench or some cord wrapped around the bearing package and a fish scale.Adjust it wrong ,and it costs you a upper gearset.

Thanks for the quick reply. I'm not replacing the gear set, only the one front seal. Since I'm reusing the old gears can I just torque the nut down to a specific value?

Edit: Strike that. I misread what you were saying. I do have the new style gearset so I have to use the rolling torque method.

While I'm at it, can I just replace the seal or should I get another yoke as well?
 

StevNimrod

Petty Officer 1st Class
Joined
Dec 13, 2008
Messages
343
Re: Alpha 1 Gen 2 Upper Yoke Seal Replacement and ?'s

Any input on the other questions?
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,344
Re: Alpha 1 Gen 2 Upper Yoke Seal Replacement and ?'s

A yoke seal leak may be from the seal cutting a groove in the yoke, rust particules getting under the seal and just damaging the seal.You wont really know untill you look at it.If it`s got a slight groove, then it needs replacing.
 
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