8 replies to this topic

[callMeMayfair]

Evening all. New member to this forum, I'm hoping someone may be able to offer some advice.

I'm restoring an 89 mini Mayfair, and have completed the engine rebuild. part of this was replacing the pot joints .

My problem is that the passenger side pot joint is extremely stiff. I find it very hard to turn.

When Test ran the engine, I noticed only the driver's side pot joint moves.  It may also be worth noting the diff was also rebuilt.

 

Things I' ve done:

 

1. After a great deal of playing around, I got the pot joint back off. I inspected the circlip and splines, both seem to be fine.

 

2. Tested the movement of the diff output without the pot on. it turns perfectly smooth.

 

3. changed the circlip and refitted the pot. it has the same stiff, un-turnable problem.

 

Things maybe to test.

 

1. try a different pot joint. 

 

As you can see my ideas list is small. I'm not sure what could be causing the joint to freeze up when hammered on? has any one else had this issue 

and had a fix? or has any inclination of where to address the issue?

 

I'm looking forward to getting the engine back in the car but would like to fix this first (its currently on a dolly). Any advice is greatly appreciated.

 

[KTS]

there's a few threads on here where others have reported similar issues..

 

i bought new pot joints and found the shafts were oversize, so much so they wouldn't even fit into the side covers

 

i had to get them cylindrically ground so they'd fit.  if you've got another pot joint handy it might be worth trying that

[Spider]

I've had the same as KTS and did the same for a fix. The oversized ones I've had were only around 1 - 2 though over, but, that's enough ! They should be 1.250".

[mad4classics]

Manufacturing defects can occur.

I've had one pot joint from a purchase of four where the outer surface had not been ground concentrically with the inner spline by a fraction - had to buy another to get me going because I'd already used the first pair.
Sent the offending pot joint back to the supplier for examination and they did issue a refund.

Confused the heck out of me for a while as it fitted a spare side cover and the spline itself was ok - just would jam up when I tried to fit to assembled diff.

Edited by mad4classics, 28 August 2021 - 06:15 AM.

[MiniMadRacer]

As a small side note, during a diff rebuild, I always try the pot joints in the side covers before assembley to check the fitment in the side cover bushes..usually the opposite is the case  for me and their is too much play so you can gtee that will leak and will need new side cover bushes.... that trial fit might help highlight future such tight / lose fitment issues as its really hard to diagnose once all fitted up

[callMeMayfair]

Thanks for the advice everyone. I hadn't wrote it for forgetting but I also had the bearings changed in the side covers. Both were reamed in with the new pots. Test turning the pots with the side covers before fitting seemed fine. ill offer up a different pot later today and look for any change.  I'll update with results just so anyone else is looking. Thanks again all.

[callMeMayfair]

UPDATE:

The new Pot joint was the culprit. It must be out a tiny bit as you all suggested. I used an old one and it spins fine. I guess ill order another as these new ones I got a while ago. I suppose a new one could have the same issue though.  Thank you again for the advice all, I can now get it ready to install back into the duchess.

[T.Harper]

Good luck. I had the same issue with one from Minispares - rang them and the guy measured on the phone and the batch he had were all about .003" too large. Perhaps order a couple from different suppliers and return those you don't use.

I had to get a local machine shop to machine mine down. Royal pain

[Spider]

Good luck. I had the same issue with one from Minispares - rang them and the guy measured on the phone and the batch he had were all about .003" too large.

 

I've found the joints from Mini Spares to be a good joint, though, I have had some over-sized ones, but only to the tune of 0.001", 0.003" is quite a step up ! The ones they were supplying about 5 - 6 years back while also good (and a few over-sized items), however, they had an odd ball boot, but it seems the latest ones will take the standard replacement item.