365 Gearbox Drive Shafts

[Dilkris]

I know this subject has been discussed at length - but I cannot find the threads now that I want them.

I am about to assemble the rear suspension (TCS) and am clear on all subjects except the issue of ensuring no oil leaks from the drive shaft jokes to the transaxle.

Here are are my questions - can someone please advise - again...  (sorry - as above, cannot find the thread  )

Question 1:
I know the importance of the O ring on the spacer, (fitted to the below), but I read somewhere that someone said add silicon to this O ring as a secondary measure. (Maybe someone was quoting Banks..?) Is this correct, recommended or not necessary.? 

Question 2:
Does the thread of the oil seal holders, for want of a better term, (ie those collars which also provides the pre-load to the diff bearings and allows adjustment of the backlash on the pinion/crown wheel), have to be treated with a thread sealant? (I hope not as I spent ages setting these up on the bench and I really don't want to move them... )

Anything else I've missed? I just want to get this right, once, as from many threads I understand this can be a "problematic" area. (Note: the body is obviously presently off the car)

     

[Pfreen]

The adjusting nut threads need a sealant.  The o ring probably does as well.  And after all of that, it will still weep oil somewhat, at least mine has the many times I have done it over the years.
I have seen teflon tape recommended for the threads.   I have tried that, and rtv and some other sealants I can't remember, but all with similar results.  It still weeps.  Maybe others on the forum have had better results.  My leakage rate is like one drip a week.  Just enough to be annoying.

[jbcollier]

The o-ring goes on the shaft first then the collar slides on and "pops" into place over the o-ring.  They can be a real #@$% to fit.  First slide the collar on without the o-ring and measure the exposed length of the output shaft.  That's your goal.  Lightly lube or grease the o-ring push the collar home.  You may need to smack it (use a soft drift, round aluminium tubing works) or press it in place ( same tune but with long lever).

There isn't any absolutely fool-proof way to seal the threads of the seal nut, sorry.  You can try cleaning it meticulously and smearing oil-proof silicon sealer.  Might not work though.  Bets practice is to mark and remove the nuts and use a non-hardening sealer like hylomar or Permetex Aviation Form-a-Gasket #3.  I understand your dilemma though.  If the transaxle is still out, then take the bell housing back off and that way you can double check your diff freeplay and pre-load.  If is all in place and this is the last thing before driving off into the sunset, then try smearing sealer and hope for the best.

[Lotuswins]

So far my best results are:

Use silicone on the nuts, but don't put them on the threads.  As John says, mark the position, and count turns removing one, then using a q-tip and brake cleaner, clean the bottom of the thread area and the face of the bearing outer race.  Put a bead of RTV silicone sealant of about 1/8 inch around on the outer race/thread interface, so when the nut is reseated it will seal against the race and the bottom of the threads.  I came across this method when I took apart a virgin 365 transaxle.

On the o-rings, measure as john says, but to lube it, use the RTV to lube both sides of the o-ring, and into the grove in the splined collar.  Let it set overnight before installing the ujoints, etc. Make sure the ujoint yoke pins drive in firm, putting pressure on the shims and collar to compress the o-ring and sealant.

So far 2 k miles on this fix, and no leakage (knock on dash)....

Jerry Rude
4005R

[Dilkris]

Thankyou Pfreen, JB and Lotuswins - I'll try all of that...
JB - the engine and transaxle are now in the car, (see photo) and whilst I understand I could remove the bellhousing to recheck back lash and pre-load - I really don't want to.....  - so it's going to be mark the seal holder positions and hope... 

[jbcollier]

As long as you are careful, it should be fine.