MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - TD 17744 On to the Gearbox

Good day to all,
Well, the engine is off to the machine shop and I have just moved on to the Gearbox. I have three initial questions.
1) The first and most disturbing is the threads on the end of the mainshaft. Two pictures are attached, showing the broken threads. The two photos are 180 degrees apart showing damage about 1/2 way around. Do you think this is serviceable? Replacing the mainshaft is NOT on my to-do list.
2) The second question is the first/reverse gear on the cluster gear. Horst Schach implies that this might be serviceable. It's not great, but it is 1st and reverse.
3) The third question involves wear on the 3rd/4th gear selector. Do you think this wear is acceptable?

I'm sure I will have more questions as I move further into the evaluation of the mainshaft gears. I already know that I need to replace the 3rd/4th shifting fork.

Thanks for your help,
Jim TD17744





JV Smith TD17744

Next two pictures




JV Smith TD17744

Jim. I have a spare TD transmission. I have not taken it apart, but the gears all look ok. If you are interested, send me an email and I will get you pictures.
Bruce Cunha

Mainshaft should be fine. The majority of threads on the nut will be on undamaged threads. Cluster fine also. At most, there may be a touch of noise from the pits in the teeth. The wear at the edges is normal. Selector does look a bit worn. George
George Butz III

If anyone needs a very nice used Cluster gear for sale $300. I also have other gearbox parts for sale.

Gary




gl krukoski

Thanks Bruce, I hope it won't come to that, but I appreciate the possibility.

George, obviously, your answers are what I had hoped for. Mainshaft is not completely dismantled yet, but gears look good so far.

3rd/4th fork is pretty worn, so I will replace that. I am hoping that I don't have to replace the 3rd/4th gear slider. I thought I would get my fork, measure the clearance and then decide.

At this point I am mostly going by Horst's book on evaluating and replacing parts. On that point, Horst pretty much recommends replacing the layshaft(cluster gear shaft), but I think mine looks good with no apparent pitting or wear. What do you think?

Any additional help from here is appreciated. I do have the DVD coming from England.

Jim
JV Smith TD17744

Thanks Gary,
Unless someone convinces me otherwise, I think I will keep my cluster gear and stop grinding 1st gear.

Do you have a good 3rd/4th selector?

Jim
JV Smith TD17744

I should have one. Send me an Email
garykrukoski(at)yahoo(dot)com

Gary
gl krukoski

Good day all,

Well, the gearbox is completely disassembled. It looks good except for the 1st/2nd sliding gear. Again, Horst Schach says this should be replaced. What do you think?

I was also going to replace shifting fork. Horst states that it should not be welded, because the weld will be softer than the original fork, resulting in premature wear and subsequent metal filings in gearbox. I have had reasoned advice to the contrary on the welding question. Thoughts here?

Thanks for your help,
Jim









JV Smith TD17744

JV, if that sliding gear is what I remember with the little balls flying everywhere when you disassemble it, it will be the very devil to reassemble without a proper tool. My friend fabricated a tool that works quite well and I'd be happy to lend it to you. Let me know if you need it.

Jud
Gowensville, SC




J K Chapin

Jud,
Thanks so much. I will take you up on the offer when the time comes. I did know that the apocalypse was coming when I took it apart, so I dismantled it inside a gallon zip-lock bag. Worked like a charm. Only a vague thought, however about how I was going to reassemble it.
Thanks again,
Jim
JV Smith TD17744

I am looking for a 1st/2nd sliding gear and 3rd/4th shifting fork. Does anyone have either or both in serviceable condition you would like to sell?
Or, can you recommend a source? Moss has new sliding gear (expensive and on back order). Abingdon has used fork (looks to have the same groove as mine)

Thanks,
Jim
JV Smith TD17744

When I had to assemble that beastie I used thick grese to hold balls and springs in location. Then I used a large hose clamp and as I screwed it tight it pushed all the balls in position.
Sanders

Good day to all,
Having received my needed parts, I am beginning to reassemble my gearbox. Following Horst Schach's advice, I ordered roller bearings. The new rollers for the 3rd gear are .935" long. The ones that came out of the 3rd gear are .979". To me, this is a significant difference.

I haven't talked to the supplier yet, but I wanted to get advice here too.

In spite of Schach's book, I am considering putting the original rollers back in the gearbox. On checking random rollers, I can't see or measure any damage.

What are the thoughts of the people here who have rebuilt their gearboxes?

Thanks for your help,
Jim TD17744
JV Smith TD17744

Another gearbox question:
The attached picture shows the space between the 1st gear and the circlip. Barrie Jones mentions a possible spacer in this space in his video. In fact, he mentions that he made a spacer, but doesn't talk about it further. Mine did not have a spacer, but I can't find any information about how much space there should be there. Almost 3mm seems like a lot of potential movement of the first gear. Any help is appreciated.

Jim TD17744

JV Smith TD17744

This thread was discussed between 08/01/2021 and 03/02/2021

MG TD TF 1500 index

This thread is from the archives. Join the live MG TD TF 1500 BBS now