Question
MG gear box
QUESTION: Hello Barrie,I have measured the end float of the sliding hub to be a total of 48 thou and made a washer as per your advice . The lay gear has a total play of 14 thou. The teeth on the sliding hub are however worse than when I first rebuilt it 6 year s ag o . I will be adding a roller cam in a month or so and anticipate more power which I did not want to create a problem for the transmission in the process.Is there a way I can send you a photo of the sliding hub so you might give me an opinion on the degree of wear and its dangers. I just watched the video again and it is hard to see the wear on the example used to show an unserviceable 1st/2nd sliding hub. Thanks
ANSWER: Hi Keith.
I can see from the photo that the gear is badly worn. You really should replace it. The problem is, the company that made them for the last 40 years has closed, so they are no longer available. You must try to find a better one. TD, TF and YB are all interchangeable. If all else fails get back to me. I may have a better one in my box of bits.
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QUESTION: Thanks for your reply Barrie, I have already "beaten the bushes " for weeks suspecting that this may be the case . The only way to get a new sliding hub will be to have it custom made for about 380 pounds. What would happen if I continued to use it after ading the new spacer to reduce hub play to .020 and correcting the .014 layshaft play down to .002?
ANSWER: So long as the new cam is not to half race spec with no low down torque, you will rarely need to use first gear, so the main problem would be reversing. If you are reasonably respectful of your 60 year old gearbox, I would expect it to work acceptably for many years to come. Just don't make a habit of reversing at high speed up a hill, and avoid Gymkhanas.
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QUESTION: Hmmm... the problem is 1st. has been quite useful since the 4.3 rear end conversion. I am investigating a specialty gear shop welding improved gear splines in and machining them down. Any thoughts ? Cheers, Keith
AnswerYou seem to have painted yourself into a corner. You need a good strong first gear. I like the idea of improved splines. Also, get the inside of the laygear polished and fit two rows of needle rollers at the tail end. You will also need a layshaft without a notch in it.
