Drive shaft UJ gear assembly pre load question

IanFS

Petty Officer 2nd Class
Joined
Apr 21, 2009
Messages
188
Hi Guys

Alpha one gen one 1988 sterndrive serial OC 345870.

I'm re assembling the the U Joint assembly to put back into the upper housing. I now require to tighten the lock nut at the end of the U joint assembly to attain the required pre load of between 6 - 10 in lbs.

I've followed the instructions in the Mercruiser manual which say that the nut should be tightened to attain the pre load mentioned above. Now I am in the process of doing it, the new Seal in the Seal carrier (that is the front seal behing the retaining ring) is creating drag.

Assembly in vice.jpg

Do you guys know if this would be written into the torque settings? This may sound like a very stupid question but the instructions are very specific in the note which says "Failure tofollow these instructions will cause premature failure" a little ambiguous I know but nevertheless important. I can't imagine they would be so dumb as to not take into account the drag on the seal??

What do you think?
 

Fishermark

Vice Admiral
Joined
Oct 19, 2003
Messages
5,617
Re: Drive shaft UJ gear assembly pre load question

I've never done it, but I seem to remember there is a different setting for doing it with a new seal versus reassembling without a new seal. Do you see anything like that in your manual? Or is my "rememberer" broken? :confused:
 

IanFS

Petty Officer 2nd Class
Joined
Apr 21, 2009
Messages
188
Re: Drive shaft UJ gear assembly pre load question

Your memory isn't bad.

What you have remembered is that for new bearings the torque is slightly different but they are concidered used once they have been rotated twice under load.

No mention of seals!!
 
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