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MG TD TF 1500 - TD trans rebuild ???

Basically I have three questions

I'm now in the process of building a stock 4 spd gearbox that was another PO project gone awry on this car. It had been taken apart and partially put back together. As the car came with 2 transmissions and 3 other loose gear sets I am trying to use the best pieces to put the partially assembled box back together. What I am noticing is that all four of my layshafts have pitting and sloughing on the small end that the reverse slider engages. I this a normal occurrence on this straight cut gear?

I am waiting for the three roller bearings and the needle bearings for the first motion to arrive so I can finish the build. I also have 5 check balls coming for the shifter detents but I only see three spots for them under the springs in the top cover. Where do the 2 others go? I see no reference to them in the WSM text of pics.

Lastly, is there supposed to be a key for the speedo worm gear fitted to the mainshaft? Again there is no mention of one in the WSM text or pics yet the gear is cut for a key as is the shaft. This trans I expect is a TD2 of TF unit as it has the 3/4 shaft bell housing. MY intact trans which I suspect is my original out of the car has the 5/8ths bellhousing.

Cheers

Bill Chasser Jr
TD4834
W. A. Chasser Jr

I've never rebuilt a TD gearbox, but I've rebuilt a great many others, so I can answer based on others that the other two balls usually go between the shifter shafts to prevent two sliders being moved at the same time. So, 3 on top, 2 in between (i.e horizontally in line with the shaft centers).
Kevin McLemore

Bill, I have found the layshaft is almost always worn through the case hardening on these gearboxes when in for a rebuild.
Question about the balls has been answered by Kevin.
The early speedo gear had no keyway, this was changed to one with a keyway on later cars.
Cheers, Hugh
H.D. Pite

Not sure if this was included but, there's a little ball in the end of the shift lever where the gear shift lever connects. Number 38 in illustration. PJ



Paul S Jennings

Thanks for the fast responses

Kevin some of the detent balls were missing so I thank you for explaining the mystery location of the 2 "eztra" balls.

Hugh, thanks for the additional verification. Seems that since this trans may be from a TD2 or TF given the bellhousing it should have a key for the speedo gear. indications are that both the shaft and gear are cut for a key yet none exists. My TD/ WSM doesn't show the key. Strange that the only extreme wear is the straight cut gear on the Layshaft/cluster gear, every thing else within the box appears nearly pristine. Even the pick up teeth on the sliders and gears look to be well cut.

Paul I have yet to take the remote shifter apart but will look for it when everything flies apart LOL

W. A. Chasser Jr

Bill,

Section F7 of the WSM explains that the key was added to the speedometer drive gear from gearbox number TW396


John

52 TD
J Scragg

Bill I have rewritten the gearbox section in the WSM based on my experience rebuilding one. I can email it to you if you like or better yet you will find it published in living colour in Issue 22 February 2014 of TTT2. You can download this free from the web. The layshaft is really cheap Bill so don't mess about, just replace it. Make yourself 4 dummy layshafts out of the others as I'm sure somebody else here could put them to good use. Cheers
Peter TD 5801
P Hehir

Thanks Peter I'll see if I can find It.
W. A. Chasser Jr

John I have a UB 101 stamped on the left front corner of the main case machined surface for the top cover. Is that the serial #? Can the gear boxes be dated by their #s? My shaft and gear are cut for a key but was either not equipped or missing most likely. It does have the distance piece which I presume is used to pinch the gear in place
W. A. Chasser Jr

This thread was discussed between 31/12/2014 and 03/01/2015

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