I have a late 2A so the swivel bearing housing and swivel pin fixings are the heavier duty ones used on the S3. I fill my shiny disco balls with EP90. The off-side does not leak. The near-side does. Both sides have new seals and retainers and very little wear to said balls.

Last night I removed the retainer and seal, turned the seal, repacked it with grease and did it back up again. No visible wear to seal. Oil in the drip tray again this morning, but I swear the oil seems to be coming from around the lower steering arm/swivel pin fixings (the double threaded bolts and nuts) rather than from around the bearing housing oil seal above.

I think I should remove the lower steering arm / swivel pin and check I fit the o-ring properly. I don't remember using mating compound since there are shims down there.. Do I also need to check these studs in some way, or apply thread sealant to them? I think they're just threaded into the base of the swivel housing casting, but not right through? So oil can't come down around those, right - only down around the swivel pin?

The attached parts diagram shows two different types of studs down there (531043 and 531494), but I don't know which holes would take which stud if that's the case - it's not entirely clear, maybe the one on the right should be used in both forward facing fixings? Can any S3 owners comment?

Assuming my seal is not leaking - am I just looking at the steering arm / swivel pin to fix this leak, or do I also need to be thinking about those studs?

I've had a very similar problem on my 2A. I changed the seal and it did not stop the leak, swivles were in very good condition ans it has leather gaiters. In my case I found 2 problems: The drain plug was sheared off and oil was leaking past the thread, I extracted the broken one and fixed that but it still leaked. I found the lower swivel arm nuts were not up to torque. Mine has the gasket and setting these bolts to the correct torque has stopped the leak. I see yours has the o ring, I don't know whether mine has or not. What did work was refilling it, clearing it with brake cleaner and lying there waiting to see what got damp. It was boring but it was what showed the leak a the control arm joint.

Thanks Rob that's helpful. So yours was leaking but it wasn't the seal in your case either. I don't have a torque for those nuts but I remember going for 'bloody tight' before bending the tabs over after a bit of road use.

I have a feeling my issue might be those studs. The 'special' ones have a chamfered half to the unthreaded section which are meant to act like locating dowels up into the swivel housing, since you don't just want to press the steering arm to the base of the swivel housing, you also want to locate it for the swivel pin. I know I did not understand that when I did these three years ago so I need to check I've done that, it certainly wouldn't help if not.

Did you smear the edge of the bearing housing seal with jointing compound? Those seals are a loose fit aren't they? Without the retainer they just drop out.. it's not like when you knock a hub seal in and flush.. or am I missing something? (edit: my seals are flush with the shiny bearing housings so they can't go in anymore, and there's no oil collecting at that lip, so if the seal is leaking it's around the edges of it behind the retainer)

The manual does say to use loctite 270 on the stud threads and sealant on the housing / steering arm interface
Which is a route for oil leakage

Mine did this i just removed a shim and it solved it

The seals seem to seal on the face rather than the OD so once they are clamped up they seal. I don't think my seal was leaking despite being very old. I cut the new one, left the spring from the old one round the axle and swapped it over, worked fine. In my case the steering arm just has shims, no gasket, but since the torque on the swivel was fine I just did the bolts up and re-fixed the tab washers tightly. I can live with a small weep, I'm happy that it all stays oily. I highly recommend the mil style leather gaiters. Mine still has them and the swivels are in great condition.

Cheers guys. Got some bits and will be seeing if I can't sort this out soon.

larger studs should be diagonally opposite each other was an attempt by Rover to reduce the movement of the arm on the swivel when stressed.
Page 4 in attached pdf referes to the larger studs when changing position of arm
Page 2 in 2nd attachement also mentions different nuts

Very helpful PDFs Blackburn, cheers!