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MG MG Y Type - Gearbox movement pin

Can anyone confirm that the castle nut on the gearbox movement pin on the underside that goes through the chassis and has s rubber bush the nut 5/16 BSF??

8ve lost mine....just want to buy the nut

Dear Dave,
I just happened to spot this while I was adding to the TCY thread. As my gearbox is now out of the car, I thought I might be able to help. However, it is in a rather inaccessible place and I am recovering from an op, so could only just about reach to try a 5/16" BSF nut on the thread. I'm afraid it wouldn't fit though - much to my surprise.
It looks as if it ought to be 5/16" BSF though. If you can bear with me over the weekend I'll try and sort out the location of the castellated nut and get back to you.
Regards, Mike.
Mike Silk

Thanks Mike...if it is 5/16 bsf i can get four off ebay for under a fiver which means ill have three as spares for any one who needs on..better than 30 pounds for the whole pin assembly!

I usually find that if the 5/16th doesn't fit it is M8 fine.
Peter Vielvoye

I also need to check if the thread of the new ones supplied by MGOCC etc are the same as original ones fitted at the factory ...they may not be ? I think they are 5/16 BSF though ??

Hi Dave.
Thought I could find the castellated nut and cup washer that came off, but I must have 'filed' it somewhere strange.
However, removed the forked rod from the bottom of the gearbox and although only the top part of the thread was undamaged, have established that the thread is indeed 5/16" BSF. I checked it against a tap and die I have of that thread.
So assuming your fitting is the same as mine, all should be well. you learn something every day!
Regards, Mike.
Mike Silk

I have bought four 5/16 bsf castle nuts off ebay = will try and fit one when they arrive - if it fits i will have three spares if any one needs one.

This thread was discussed between 31/05/2019 and 04/06/2019

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