Does the convex shaped end of the inner pot joint (which holds the bearings) sit tight against the end of the 'pot' nearest to the diff?
I've had an issue with some pot joints in where the caps sealing them from the diff have come out, letting the CV boot fill with engine oil.
This is what has happened. I've got some new plugs but they are deeper, I am wondering if they need to be flush with the inside or whether they can be proud of the back face.
Classic Mini Steering Drop Brackets here Kiddspeed
That cap popping off was a serious & common problem with a batch made by /for a well known Mini Specialist in the Lancashire area. A real pain in the arse it is too. There are also some other ones that have the circlip groove machined wrong making sure the circlip wont engage causing the CV joint to come off in use.
I personally would NOT replace the cap I'd replace the joint with a good one.
Better to contact a specialist & get their assurance the ones they are selling you are correct & CHECK that they fit correctly during the build.
It is now rebuilt with new caps replaced and fitted with bearing fit loctite.
I couldn't be guaranteed that other ones available would be much better so I'm going to try these and see how I get on whilst looking for a genuine set. The original ones off the car were binned purely because I couldn't get the rust off them and they looked pants.
I have a feeling that the caps might have been knocked out when the pots were first fitted and we just knocked them on with a piece of wood and a bog hammer until they sat against the diff housing.
Classic Mini Steering Drop Brackets here Kiddspeed