General TR Tranny Fork alinement problems & TR3 shifter in a TR6 tranny

[Got_All_4]

Just finished freshening up my TR6 J-type tranny gear box that is going into my TR3A. I purchased it in unknown condition. All new bearings, synchro, 3rd gear, counter shafts and thrust washers. Everything spins and shifts nicely until I put the top on. Immediately I noticed that the forks didn't line up and had to bump the top forward to get everything to drop in. Put some bolts in and tried to go through the gears. 1st and 2nd are almost locked up. 3rd gear spins the best and if I pull too far back into 4th it locks up too. I noticed that when aliening up the top the bolt holes were about a 1/2 hole off. That's when I had to bump it forward to drop it in. The problem shows up in the forks. When you place the forks on top of the shifting hubs the same half hole distance is there. I also have a 4A tranny apart that is in poor shape and if I place the top from it on the 6 tranny everything lines up and shifts fine. Unfortunately it's not a overdrive top and is not usable.
I have the shifter leaver from my TR3 in it and Scott at Team Triumph thinks it's the problem. I think I read somewhere that Randall has his TR3 shifter in his J-type tranny. correct me if I wrong.
The pic is the 2 tops together showing the difference in the fork spacing. Not sure if all TR trannys use the same forks but both of these sets have the same Standpart number on them. It's about 3/16" off.

 

[TR3driver]

I do have a TR3 lever on my TR6 gearbox, but it has an A-type OD (which shouldn't make any difference to the shifter) and also a TR3 top cover casting (with TR6 shafts & forks installed). However, which lever shouldn't make any difference. The business end of all the shift levers is the same, plus the shift interlock in the top cover has to line up regardless of what the lever does. You could double-check that by removing the lever entirely, making sure all 3 shafts are in the neutral position, and then see what happens when you install the cover. I would also double-check that the shift interlock is working on all 3 shafts (ie if any one shaft is out of neutral, neither other shaft will move from neutral). It's really easy for the pin or one of the balls to get dislodged while assembling the cover.

The shafts are different between the 3 synchro TR2-3 box and the TR4-6 box. Sounds like your top cover may have a mixture of parts. Since you have a top cover that does work, I'd start swapping parts until the problem moves. Or just compare parts side-by-side. 3/16" should be easy to see.

PS, I believe I've got the template somewhere for adding the OD switch holes. Let me know if you want to go that route. Although the tap is not found in most sets, some calling around found one on a local shelf for not too much money. ISTR it was only $15 or so, but that was probably 20 years ago.

 

[Got_All_4]

I didn't take the cover apart. When I cleaned everything the cover shafts looked new and in perfect alignment . (Maybe the PO bought one incorrect shaft) This tranny has been apart several times from all of the hammer and pry marks so maybe this has been the problem all along with it. I have a 69 TR6 with a A-type tranny. I'll take the cover off of it first and see how it fits. If it does fit I can eliminate problems in the gear box and take the cover apart and lay out the shafts to see if everything matches up. I'm assuming that the neutral position on the shafts would all line up and if one is out of position then that would be the problem child?

 

[TR3driver]

Yeah, that's the idea.

 

[M_Pied_Lourd]

Fwiw, I had shifter problems once in a TR6 tranny where one of the top switches for the OD ovalled out on the inside and caused the ball to jamb the rod. It is my understanding that these switches need to be set to the correct depth with shims/fibre washers....

Cheers
Tush

 

[Got_All_4]

Well it took me a while (only 7 months) but I took the top cover off my 69 TR6 overdrive and mounted it on the JType I'm working on and it fit just fine. Was able to go through the gears and nothing locked up. I took the TR3 shifter and put it in the 69 top and it locked up just like the Jtype cover did. So the problem is the two aren't compatible. Looking for some advice here. Definitely don't want the TR6 shifter in my TR3.

 

[Marvin Gruber]

Post a picture of the TR3 shifter. It should work fine in the TR6 shifter. Does your TR6 shifter top have pins or a bolt that goes across the whole shifter assembly.

Marv

 

[Got_All_4]

Pins. I used the 1/4" bolt from the TR3 tranny to go through the shifter and the case.

 

[Got_All_4]

TR3 shifter

 

[M_Pied_Lourd]

Hmmm, odd. I have a TR3 shifter on my TR6 trans with the original A type fitted and it works fine...

Cheers
Tush

 

[Got_All_4]

Ok found another TR3 shifter handle although better I could actually go from 1st to 2nd several times with no binding and the same for 3rd and 4th. But when I try to go back to 1st everything binds up and forget about reverse engaging. I did notice that the handle is hollow and there is a seam just above the ball. Looks like the gear shift handle and the lower part with the ball are 2 separate pieces. Has anyone been successful separating these two pieces? I'm thinking of getting a TR6 shifter and screwing the Tr3 handle onto the TR6 lower piece with the ball. The one from the 69 tranny has the same seam.

 

[TR3driver]

Are you sure your shift interlock works right? I don't see how any difference in the shift lever could make it bind sometimes and not others (not to mention that I'm convinced they do interchange). I think your binding has to be because one of the rails is not fully returning to the neutral position.

I have seen someone cut the lever and weld it back together, but it sure made a mess of the chrome. Easier to modify a cover for the OD switches, IMO. But AFAIK only a few very early TR3s were supplied with the two piece lever, and it wasn't hollow.

FWIW, I believe the intention with the hollow lever was to move the OD switch to the shift knob; but that never actually happened with the TR line. Stags and late Spitfires had it, though.

 

[M_Pied_Lourd]

Take the top cover switches out and try shifting it with them out.

Cheers
Tush

 

[CJD]

The shift levers and covers are completely interchangeable. The difference between the 3 and 4 synchro covers is the shift forks. There is a slight difference between them when they had to change the way reverse engages on the later boxes.

 

[TR3driver]

The difference between the 3 and 4 synchro covers is the shift forks.

And the rails too, I believe. In particular, 1st gear is farther forward (at the knob) on a 3 synchro box, so the detent notch is in a different location.

 

[Got_All_4]

Thinking back on the last time I put the cover on I don't remember engaging the reverse selector fork and that maybe the reason reverse is jamming. I was thinking the same thing Randal was about the interlock not lining up properly but the shifter from the 69 A-type cover worked perfectly in the J-type cover and putting the TR3 shifter in the A-type cover jammed it up. Mainly 1st and 2nd gears. Now as far as the TR3 shifters both of mine are hollow as you can see in the pics. The spike goes in 4" and the pic isn't clear but the TR6 shifter has that same ring on it where it looks like it comes apart.
I'll have to play with this again on Sunday and maybe take the switches out and the inner locks and see what happens.

 

[CJD]

And the rails too, I believe. In particular, 1st gear is farther forward (at the knob) on a 3 synchro box, so the detent notch is in a different location.

True! The neutral detent is in the same location, but the rail for a non-synchro requires more throw to engage 1st, so the 1st gear notch is not symetrically the same distance from the neutral detent.


Here you can see the rail for 1/2 has an obvious farther throw for the 1st gear locating notch. It may fit in a synchro box, but would not engage the detent to hold the rail in gear.

 

[Got_All_4]

Well I decided to take the A type tranny out of the 69 TR6 which I know is not original to the car. I toyed with using it instead of the J type last year in the TR3. Well now that is what I'm going to do. Putting them side by side on the bench and doing the swaps of the covers came out with the same results. Then a miracle happened. I put my original Tr3 shifter in the A type and it worked. Then I put the new Tr6 shifter into the J type and it worked. Don't ask me how or why but I put the cover gasket on the J type and that is now going aside (that will go into the TR6) and I'll disassemble the A type and do a update. I'll post a new question on what to get. Thanks for all the help.