MG Car Repair: mg td third gear jump, mg car club, drive flange

Question
Hello. I have recommended to consult from the bbs forum and thank you for your attention.
I have an MG TD, 1952 with the following problem: When slowing or decrease rpm in third gear, third gear jumps. However, when I accelerate and climb rpm, third gear does not jump. I have consulted several pages and forums but can not find unanimous response. I live in southern Spain. Here we have a climate for MG TD drive, but do not have spares. Time consuming and expensive to get them to have the car in the shop. I locate the fault correctly, or at least more successful.
In the forums the answers are varied: See general wear, lockout balls, weak springs, worn bearings, washers, laygear end float, drive flange nut loose, selector mechanism in disrepair, poorly positioned sliding hub. And recommendations: Add a detent in the rail 1 / 2. Add a shim between the ring and the main bearing.

Please with his experience and good to know, what is the best solution?.

Regards.
Gabriel.

Answer
Hi Gabriel.  This is a common problem with the TD/TF gearbox.  Unfortunately, there could be many reasons why the gearbox jumps out of gear on the over-run in 3rd gear.  The only solution is to strip the gearbox and inspect the components for wear and damage, then to reassemble with the correct clearances.  This is a long and complicated process, which I cannot explain in a short e-mail.

I have produced a 2-hour video (DVD) showing how to strip and rebuild an MG TD/TF gearbox.  It is for sale from the MG Car Club T Register.  

It can be bought from www.tregister.org