General TR This Happened Twice [TR6 tranny in a TR3]

I've got a 1970 TR6 over drive tranny with the TR3 straight shifter in my 60 TR3A and this happened to me yesterday. Basically it's the second time. The first is when I first test drove the conversion and out of habit I lifted the shifter to go into reverse and the anti rattle ball came out and jammed the linkage. I was told to never do that because the TR6s weren't designed to lift the shifter when going into reverse. True. So yesterday getting the 3 out for the first time this spring and having some clutch issues (I'll keep it short). I had a grip on the shifter while in 2nd when the clutch engaged the car lurched forward and me backwards holding onto the shifter and pulled it out of the linkage stuck in second gear and no clutch.

I have noticed that TR6 trannys have studs on the sides that hold the shifter ball in place and don't go all the way through the ball. Wonder if that is the fix so they still rock side to side and can't lift? The slot for the TR3 shifter handle where the bolt goes through is elongated so it can go up over the hump in the linkage for reverse. So if I close up that gap it could eliminated this problem?
Has any one had this problem after converting and how did you fix it.

I've not had the problem (my TR6 gearbox has a TR3 top cover installed), but I don't think the pegs would help your situation. The Stag uses the same pegs, but IIRC they don't stop the ball from moving up.

Instead, I'd be putting a spacer between the top of the ball and the curved piece on top of the big spring, to limit how far the ball can come up. I think it still has to come up some, but not as far as the slot allows. There's a service note about putting a length of heater hose in that location, which likely would solve your problem.

Or, I see TRF has the early reverse shift cup for $20, which might be another solution. Early TR6 did require the lever to be lifted, I believe.

Or, the route I took was to install the TR6 shift rails & forks into a TR3 top cover. My desire was to retain the dipstick, but it also side-stepped your problem. Ask around locally, someone probably has a spare cover they'd sell cheap. I gave away an entire TR3 box to a friend last year, who told me he usually pays $30 for rebuildable cores!

PS, here's an illustration from the TR6 ROM. As you can maybe see, the slots for the pegs are open at the bottom, but the ball extends up through the spring to limit how far the ball can come up.

Is the TR6 Over drive transmission a good candidate to replace a TR3 transmission? Maybe easier to locate.

David

I’ve never had an issue with mine...it has a TR6 trans in it with the A type that came originally in the car...it also has the TR3 shift lever installed. It is a pleasure to drive with this combination.

Cheers,
Tush

Hello Tush

My short driving experience with my TR3A has shown that an overdrive would be a great benefit. Will have to start looking out for a TR6 OD transmission. Failing that find Toyota one for the 5 speed conversion.

David

DavidApp said:

Is the TR6 Over drive transmission a good candidate to replace a TR3 transmission? Maybe easier to locate.

David

Click to expand...

There are a few minor changes to be made, but nothing major, as long as you get one of the earlier A-type overdrives.

The later J-type sits farther back, which means fabricating a new cross member and maybe trimming the frame just a bit; but can be done. Oh yeah, it also screws up the speedometer calibration, unless you change the gears inside the OD or get a ratio converter.

I've been running this one (which is a combination of TR3, TR4 and TR6 parts) since the early 90s. It needs freshening again (2nd gear synchro is mostly worn out), but has worked out well for me.

Hello Randall

Thank you.

David

David, The OD in my car along with Super pro suspension bushings, removing and lubricating the rear springs with new bushings transformed the rid of my TR3.

My gearbox must still look like this illustration in Bentley because there's no way I can get my transmission into R without a little lift of the lever....and I've never lost the anti rattle components doing so.
.

FWIW, Ken, the reverse selector changed at some point (or at least there were two different versions, maybe not a single change point). Eg,
https://trf.zeni.net/TR6bluebook/83.php?s_wt=1920&s_ht=1200

The "later" selector, I believe, had a ramp rather than the sharp corner shown in the ROM (and found on earlier TRs); such that it was no longer necessary to lift the knob to get into reverse. Still takes some side force, to get the lever up the ramp, but not a great deal. (I rather suspect that a lot of earlier selectors are worn enough in that area to produce the same effect.)

As shown in your diagram, with the original TR6 shift lever, the top of the ball has a smaller section that sticks up through the spring, and limits how far the ball can come up. But, the OP has a TR3 shift lever in a TR6 top cover, and the TR3 shift lever is shaped differently in that area, which allows it to come up higher.
https://www.triumphexp.com/phile/6/40675/TR3.JPG

So you're quite right, the problem does not happen until you start mixing components. IMO, YMMV, etc.

My 250 takes a good pop to the right to get it into reverse. 4 speed. Suppose that ramp is't worn in yet. All the gears seem fairly tight with 60k+ on it. I treated the tr3 the same way when I first started driving it before I knew better. Learned that lesson when I got a new rubber gear shift that you can read the LIFT printed on it. I like the rubber hose fix that was suggested and going to take a good look at it this weekend. Keep the fixes coming!
Don't know what year the tranny was made. It came out of my 69 TR6 and it was a replacement for that car. Had some bone yard printing on it. May have said 1970 TR6. I've got a 70 A type ready to be rebuilt and another overdrive tranny with a J-type where I rebuilt the gear box and one of my customers is rebuilding the OD. He was a Triumph tech in the day. Trying to decide which is going in the 69 TR6 and the other in the TR250. Now the 250 has a later TR6 frame under it so the J-type should be a drop in.

I have a TR250, as far as I know original (rebuilt) transmission, I have never had to lift to engage reverse. The car had about 90k miles on it when I bought it. Does the need to lift to engage go away as the gearbox and linkage wears in.

Not mine in my 50,000 miles of driving it...I'm not sure how many miles the PO put on it before that, but I think I remember him saying the transmision was rebuilt and J type added by Quantum Mechanics Ltd.

I rebuilt my TR2 tranny with parts from the 4' tall "Christmas" pile I bought for $100. It had many, many different shifter links from many Triumph generations. I selected a reverse rod with the worn ramp...at least I thought it was worn. Now that I read this thread, I suspect it was a later rod intentionally ground that way. It slides relatively easily into reverse. In fact, too easily for my liking. In normal shifting it is no problem shifting 3 to 4. But in a rush, when muscling it into 4th, it'll slide over and catch reverse.

So...having driven both, I much prefer the lift action to prevent inadvertent engagement of reverse. I grew up with Chevy race shifters, which totally locked out reverse. I like the lock outs even better! Of course, we were ham fisting Muncie rock crushers back then. These little trannies won't take that kind of abuse.

I have the TR6 box with A type OD and it had the sloped ramp for reverse and I thought it was worn out so I changed the shifter end for the one out of my old box. I have used the 3A shift stick with the 1/4" bolt and haven't had any issues with it losing the anti-rattle cup and spring.
If you are considering using the two studs to hold the stick you will need to change the size of the ends that engage with the ball because they are 5/16" and the slot is 1/4".

Graham

Ya thanks Graham. That's why I'm going to try the hose piece first that Randal suggested. Getting into more work and potential problems with the studs.

Here is the fix. Took me a while but I think I have Randal to thank. Did the rubber hose insert. Took a few trimming to make it work. Spring goes in first then the hose on top. After assembly and a quick drive I noticed the hose in a short time would be working it's way through the gap in the spring cover. Found a closer one the fits better but also had to put a copper washer on top to eliminate the problem. Works perfect but now the OD doesn't work. Where does it end?

Got_All_4 said:

Where does it end?

Click to expand...

I could answer that, but you wouldn't like it!

Last year, I carefully rebuilt the hydraulic pump in my 49 Ferguson (with the TR motor). New pistons, new cylinders, new valves, the works. It worked great for a few months, then quit. Yesterday, I finally discovered a stream of oil gushing from the side of the pump. So, it's got to come out again. Fortunately I only put two gallons of fresh oil it, not all it holds.