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MG TD TF 1500 - TC Gearbox Rebuild

I rebuilt my TC (body and mechanicals) 27 years ago save for the gearbox as a visual inspection showed all to be ok. Now, 12,000 miles later, it has developed a whine in the three indirect gears. Synchros are fine so I suspect bearings. As a gearbox is something that I have never tackled I would appreciate advice on what I should be looking for, pitfalls and such please.
Posting on this site as it receives much more traffic than the TC one.
Many thanks
Peter (TC9356)
Peter Malkin

I have some info on the TD box Peter. Not sure if they are similar enough to be of any use to you though. I'll email it to you anyway.
Cheers
Peter TD 5801
P Hehir

http://www.mgccyregister.co.uk/technical-information/the-xpag-files/xpag-rebuilds/xpag-gearbox-rebuild/xpag-gearbox-rebuild-part-one-introduction/



Its not that complicated apart from the usual indent and rod layout stuff.
mog

Roger,

TC owners use www.mg-tabc.org for their informational site. There's a forum there plus an email list.

I've rebuilt a TC gear box,,,not a lot of parts available but bearings, etc., are. Best place for everything TC is: www.fromtheframup.com

Gene
Gene Gillam

This is the best article on the subject I know:

http://www.mg-tabc.org/library/gearbox/Rebuilding_The_TC_Gearbox.htm

TC boxes are renowned for their strength - far more durable than TD/TF boxes. I've seen a number of TD race cars into which TC gearboxes have been fitted, starting with Ken Miles' two cars.

If you are willing and able to, it would make an interesting article for TTT2; firsthand experience is always very worthwhile to document.

Take lots of pictures, lay everything out, and make a list as you disassemble. Measure everything, especially the needle bearings - as Gene notes, parts are scarce for anything other than bearings.

Let us know if we can help.

Tom Lange
MGT Repair
t lange

Peter

Because I have a TC gearbox installed by a PO in my TF I have kept this reference:

http://www.mg-tabc.org/library/gearbox/TC_Gearbox.htm

As I was posting I see Tom has also pointed you in the same direction, smoke and mirrors travels slower from downunder.

Graeme
G Evans

Peter

Another memory flash, I know someone in Newcastle, NSW that has rebuilt many of these boxes, if you get stuck I am sure I can put you in touch.

Graeme
G Evans

A whine may indicate chipped or missing teeth on a gear(s). Is the oil level correct in the box?
Regards, tom
tm peterson

Whoops...that should have been www.fromtheframeup.com
Gene Gillam

Thank you all for assistance. I'll maintain a record of the rebuild when I get around to doing it - probably after winter.
Tom - oil level ok.
Peter Malkin

Peter -

I am removing the gearbox in my TF tonight. Third time in two years. I rebuilt it using mostly new or good used parts. But I have noise and hard shifting, so I'm looking inside again. Trying to get it back together in time to drive it to GoF-South on Apr 21.

My biggest problem was my inexperience. I couldn't recognize problems (if any) when I reassembled the gearbox. Might help to ask a friend with TC gearbox experience to watch you as you assemble it.

My second biggest problem was finding reliable specs about clearances and tolerances.

I enjoyed the experience. Just wish that I didn't have to look inside again.

Lonnie
TF7211
LM Cook

Thanks Lonnie. The links that I have been given are terrific.
Peter (TC9356)
Peter Malkin

Hi Peter,

A couple of bits of info' which might be of help if you find that you need any bits that can't be bought new. The Riley 1 1/2 gearbox is very similar to the TC. The differences are in the first motion shaft spline length and the ratios. Tooth numbers on first and second are the same but third is SOMETIMES different. Casing, first gear, second gear, reverse, sliding members, selectors and other trinkets are the same.

I know that TD/TF gear box info' is irrelevant to you but for other readers I noticed that the mgccyregister website, mentioned in an earlier post, stated that the Wolseley 4/44 internals fit the TD/TF box. This is NOT the case. In all the Wolseley boxes I have seen internals are very similar but are all about half an inch too long for the TD/TF box. A bit frustrating as I have a 4/44 laygear, in PERFECT condition, in my shed. I have heard of 4/44 internals being fitted to a TD/TF box, but it had to be machined out internally to make room.

TC boxes are very strong but even when in good condition they tend to get gear-lever rattle. The TD/TF box has a longer mainshaft and an extra bearing at the rear of the back extension and I think this was a design improvement which made them quieter.

Good luck with the rebuild.

Bob Schapel
R L Schapel

Some general part numbers would be helpful. Bearings and seals? 6307 is one of two transmission front/rear "main" bearings.

Unfortunately all these articles are old, and trying to match old proprietary bearing and seal numbers is a no go. Moss numbers, for instance, are not helpful unless you want to buy your bearings from them.

Once you have it all apart it is simple to measure the bearing/seals, etc and come up with numbers. Nice to have those things ahead of time.
D mckellar

http://www.skf.com/group/products/bearings-units-housings/ball-bearings/deep-groove-ball-bearings/single-row-deep-groove-ball-bearings/single-row/index.html?designation=6307
mog

This thread was discussed between 10/04/2016 and 14/04/2016

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