What is the acceptable clearance on the diff side plate bush?
This being the bush the pot joint shaft fits into.
From memory I recall a figure of 1 thou.
I have 3 thou and doubt it is worth changing. The bush condition looks good.
What are peoples thoughts?
Thanks.

I give them .001" clearance when I replace them.
I clock the cover up in a 4 jaw chuck so the seal diameter and the bush run true, then bore it.
If the yoke/pot joint is worn on the outside, machine that true first, then bore the bush to suit.
The new bushes are supplied .007" undersized to allow this.
The seal still works fine if the diameter of the yoke/pot joint is a few thou undersize.

re your question, .003" clearance is not too bad, grab the yoke or pot joint and tug it up and down. If it moves heaps replace it.
The LH one wears faster because of the greater angle on the shorter driveshaft.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

At the risk of being yelled at for reviving an old thread, I'm seeking some clarification.

In the process of reconditioning my rod change, pot joint, gearbox. The side plates I have (6 of them!) are all "slightly floppy" on the new pot joint. New pot joint measures at exactly 1.250" diameter and I have around 0.0025" clearance measured in all 6 plates, give or take half a thou.

My first question, is should I be bothered to fit and ream the new bushes I have or not? In other words, is 2.5 thou too much?

Both of the below mentioned "how to" videos mention 1 thou as being idela, so maybe 2,5 is in fact too much.

My second, and possibly more important, question concerns the orientation of the bushes.

5 of the 6 have the hole in the bush opposite the two grooves in the inside of the plate, whiile one has the hole positioned over one of the grooves. Given that (I assume) these grooves are to allow lubrication of the bush then it seems to me that the odd one out makes more sense. Oil passing through one of the grooves would be then carried around the inside of the bush in the channels cast therein. As fitted to 5 of the 6, oil can only get to the inner bits of the bush from the sides, in which case one asks why there's a hole at all? Surely it would make more sense for the centre of the bush to receive some as well?

I may have completely the wrong end of the stick here of course, but if I do bite the bullet and go ahead with fitting the new bushes to a pair of plates then I don't want to perpetuate what may be a previous error on somone's part.

Interestingly, there are two videos on Youtube detailing the process. One specifically says that the hole should be opposite the grooves, the other makes no mention of it, but shows it fitted with the hole over the groove.

One advocates machining on a lathe, the other reaming by hand. I guess this is just a matter of what resources one has.

Please, Brains Trust. Alleviate my confusion if you can.

Thanks in anticipation of alleviation! Pottsy.

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Smile Up at The Trucks!

You won't keep the bush square if reaming by hand. Then the shaft will bind up as it turns.
With 2-1/2 thou clearance I would leave them alone.

Regards the bush's hole position, it can go anywhere. Usually they seem to be horizontal.

Regarding seals I have found the ones supplied in gasket kits now are not tight in the cover, they need some Loctite 515 or similar to retain them.
OTOH seals I bought from a bearing shop yesterday are a nice tight fit.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Thanks Doc. As always a voice of reason.

I shall proceed on to other aspects of the rebuild with a light heart and a song in my step.

Cheers, and thanks again, Pottsy.

_________________
Smile Up at The Trucks!