• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Slack in Differential

Share this page

Mickey Richaud

Mickey Richaud

Moderator
Staff member
Gold
Country flag
Offline
Trying to sort out all the little "surprises" in my B restoration, and found that I've got the infamous "clunk" in the diff. when starting out in reverse and first.

Any tips on replacing the thrust washers? Do I need all of them? Part nos. 65 & 67 here:

https://mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=29022

Curious: the drawing only shows 1 thrust washer for the pinion, but listing calls for 2. What's up with that?

Aside from the slack, diff sounds fine - no bearing noise. Any other pieces I need to replace while I'm in there?

Thanks,
Mickey
 
Hi Mickey,
The drawing only shows one washer because the other half of the parts are not illustrated. They are a mirror image of the parts shown.

Replacing the washers mentioned "might" solve the problem. There are several other places that could be causing the slack, such as, ring gear side to side location, pinion gear depth setting, worn axle splines, pinion drive flange not tight, worn U joints, & worn splines on knockoff type wheels, which I assume that you don't have.

If I were going to the trouble to replace the washers that you mentioned, I would certainly do a complete check & measurement of the ring gear side to side location, pinion depth setting, all gear & bearing conditions, & ring to pinion backlash setting, in order to determine exactly where the slack is. Since you said that it isn't making any noise, you "might" hit it lucky & fix it with replacement of the washers, maybe not.

Do chech the pinion drive flange & U joints first.
D
 
Thanks, Dave -

U-joints are new. As it happens, I had to scrap the body that I started with, and bought this rolling chassis from Tony Barnhill. I've got the rear end that went with the engine and tranny, which were transplanted into this body. My guess is that it may be in better shape anyway. Will probably check it out, replace whatever's necessary and swap it in. Probably should have done that to begin with, but didn't know the condition of the rear end beforehand. At least I kept the old pieces!

Mickey
 
Replace both thrust washers, and both copper washers behind the spider gears, and put in a new split pin. I have done two of them, it is pretty easy. Go here for pics and more info.
web page
 
Thanks, Mark! That's helpful. As in my last post, I'm probably going to redo the diff that's out of the car, and swap 'em out, springs and all.

Mickey
 
Thanks, em - that's the same page Mark referenced in his post above. Good info, and you bet I'll mark it!

/ubbthreads/images/graemlins/cheers.gif Mickey
 
Update:

ARRRGH!

OK, I feel better now. Got everything apart and trying to reinstall the gears. The two pinion gears have to be aligned perfectly in order to replace the pinion pin. IMPOSSIBLE! Well, probably not, but it sure is elusive. I can get them back in, and they appear to be close, but no way will the pin (which, by the way is a bear to remove or put back - why did I expect otherwise?) go back in place. No matter how much I finesse the axle shafts, the hole for the second pinion gear is about 1/8" out of line.

By the way, I'm doing this on a rear end that is out of the car - no way I could do this "in situ".

Any suggestions on reassembly?

Mickey
 
YEEHAW! Gave it one more try, and it slipped together perfectly. Must have been the time-out. Now it's clean up and repaint, then will swap it in next time I have a day to work on it.

Mickey
 
Back
Top