When I took the car out this time for a few laps around the block, I hooked the speed O-- but no reading on the gauge. I unhooked the cable and the cable was not turning. The trans is an OD with a new longer cable I purchased from TRF. Kinda looking for a starting point and any information about OD hook ups if they are different on the trans. Hopefully, I can leave the transmission in place. Perhaps the cable is not long enough, but that does not sound correct. All ideas welcome
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TR2/3/3A Speed O not working
- Thread starter sp53
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TR3driver
Great Pumpkin - R.I.P
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The connection is only different in that it's in a different location. I'd probably start by making sure the new inner cable protrudes from the outer cable far enough to engage the drive gear on the overdrive. Turn the drive end, and check that the speedo end turns.
If that all looks OK, next step is to pull the speedo pinion and bushing out of the OD. I'm pretty sure it can be done with the OD still in the car (but haven't tried it myself). There's a retaining bolt that comes out, then it's advisable to use the knurled collar from an old cable (either speedo or tach will work) to protect the threads and provide a place to pry the bushing out. (Photo courtesy Buckeye Triumphs)
If that all looks OK, next step is to pull the speedo pinion and bushing out of the OD. I'm pretty sure it can be done with the OD still in the car (but haven't tried it myself). There's a retaining bolt that comes out, then it's advisable to use the knurled collar from an old cable (either speedo or tach will work) to protect the threads and provide a place to pry the bushing out. (Photo courtesy Buckeye Triumphs)
Thanks Randall I will get a look in the morning. No David, I used the 96 inch cable and used a big loop and come through the shifting tunnel at the rubber boot bump. I think that is what the bump in the rubber boot is for by the E brake, but I have never installed an OD before.
TR3driver
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I checked, according to the factory catalogs, the angle drive wasn't used on TR4, introduced on TR4A (when they moved the handbrake location and eliminated the holes where the old cable ran). On the 4A with the angle drive, the longer cable is not required.
I went and undid the cable at the trans then turn the cable by hand to make sure it was in one piece and it was. Next I took an old cable put that in the trans and was able to spin the cable by hand. That does not sound correct. I am not sure how much should be sticking out of my new cable, but again I could turn the trans end by hand, so not sure.
It has been over 20 years since I have rebuilt a non-OD and I cannot remember exactly how the speedos were driven. I will have to pull the tunnel cover to access the speedo bearing assembly and hopefully the problem is in that if I can get it out. I do have some old speedo drives from non- OD trans and hopefully I can come up with something.
It has been over 20 years since I have rebuilt a non-OD and I cannot remember exactly how the speedos were driven. I will have to pull the tunnel cover to access the speedo bearing assembly and hopefully the problem is in that if I can get it out. I do have some old speedo drives from non- OD trans and hopefully I can come up with something.
TR3driver
Great Pumpkin - R.I.P
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Pretty simple; there is a worm gear cut into the output shaft (which for an overdrive is one piece with the annulus).
Then the bushing carries a shaft & gear that meshes with the gear on the output shaft.
I forget the tooth counts offhand, but the worm is multi-start. The effective ratio is 5:2, meaning the speedo cable should turn twice for every 5 turns of the drive shaft.
Later on, with the J-type, the worm became a separate gear and the ratio could be changed. But for an A-type, it's always 5:2 (or 2.5:1 if you prefer).
Then the bushing carries a shaft & gear that meshes with the gear on the output shaft.
I forget the tooth counts offhand, but the worm is multi-start. The effective ratio is 5:2, meaning the speedo cable should turn twice for every 5 turns of the drive shaft.
Later on, with the J-type, the worm became a separate gear and the ratio could be changed. But for an A-type, it's always 5:2 (or 2.5:1 if you prefer).
TR3driver
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Yeah, pretty much. Principles are the same, of course, but the parts are different; ratios too. Are you working on a J-type?
Speedo drive is geared directly to output shaft; should be impossible to turn the drive unless the output shaft turns as well.
I don't recall a shear pin, but it might be there. If something breaks, it's usually the teeth on the driven gear.
Speedo drive is geared directly to output shaft; should be impossible to turn the drive unless the output shaft turns as well.
I don't recall a shear pin, but it might be there. If something breaks, it's usually the teeth on the driven gear.
I dug out a non-OD setup and they measure and look the same as OD—But the one in the car will not give any. There is a way to remove the inner brass section from the outer with flat side on the outer edge, but again I am not sure that will help any. Perhaps some kind of pulling tool would fit in there. I put a small amount of WD in the hole where the bolt came out on the top of case and I am waiting for that to work. Plus I was able to get some leverage by using the aluminum end piece and pry against that-- but no joy. There must be another way with some kind of specialty tool. Where is Geo he has all the cool pics of cool tools. I have been tapping lightly with some wood trying to cause some vibration. I hope one of those rebuilder guys might have a gear he would give up, but heck it might worse inside. I guess I should have tried to rebuild the OD in the beginning, but I was overwhelmed with learning body work
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Well I killed the brass end on it, but I pray a non-OD is the same. My thoughts are aluminum oxidized to brass. Anyways I do have the bushing turning left to right about a ¼ turn, but it will not head out of the casing. Plus there is no way to get any oil between the case and the bushing and the bushing is a few inches long into the case. Any ideas out there? I am afraid to heat the brass because I do not know if it would do more harm than good. I guess keep trying to work it out left to right and cry for help.
CJD
Yoda
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That is common for the assembly to get stuck. If you have already damaged it, then just use big vice grips and twist it out. It does have a lock bolt in the tranny, so make sure that is removed first, or it’ll never come out. Don’t feel bad...some of those are so stuck they will never come out without damaging them. I am sure it is galvanic action with the aluminum, as you suggested.
There is an inner and outer sleeve to the brass assembly. If you look closely, there is a pin drilled and driven through to hold the 2 together, though. Before you can separate them, the pin must be drilled or it will damage the soft brass threads. Inside there is a seal that you can replace, if you want to.
I find it interesting that the assembly would strip. It is normally pretty stout.
You are in luck, in that the assembly is common throughout the TR2/3 range of trannies, with and w/o the OD.
There is an inner and outer sleeve to the brass assembly. If you look closely, there is a pin drilled and driven through to hold the 2 together, though. Before you can separate them, the pin must be drilled or it will damage the soft brass threads. Inside there is a seal that you can replace, if you want to.
I find it interesting that the assembly would strip. It is normally pretty stout.
You are in luck, in that the assembly is common throughout the TR2/3 range of trannies, with and w/o the OD.
Thanks John I truly appreciate that a lot. The square drive at the end was damaged and broken off at the very end--- somehow, and I believe it was blown out from an old broken cable, but I do not know. That is what accelerated my efforts to remove the assembly. I used a slim 5/8 wrench on the end bushings and separated the two brass pieces at the end and saw the damage to the tip-- then I put the aluminum end on and pinched that between the brass and 5/8 wrench then smacked it with a big screw driver down low, but it cracked the brass at the end.
Anyways yes I have gone to vise grips and got it to turn some. Probably 5 to 10 years ago, I would have twisted and turned with down pressure and get out more easily. Now I am going to use more leverage. One problem I see is because OD speedo assembly points down with really no way to get oil in there except if I had it apart-- maybe, but heck it is so oxidized and tight no oil might ever get in. Would you put heat to the brass if it was trashed or stay with muscling it out?
steve
Anyways yes I have gone to vise grips and got it to turn some. Probably 5 to 10 years ago, I would have twisted and turned with down pressure and get out more easily. Now I am going to use more leverage. One problem I see is because OD speedo assembly points down with really no way to get oil in there except if I had it apart-- maybe, but heck it is so oxidized and tight no oil might ever get in. Would you put heat to the brass if it was trashed or stay with muscling it out?
steve
TR3driver
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It is, on an A-type.
CJD
Yoda
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Heat is a tough call. Steel and aluminum have a big difference in expansion coefficients, but I think brass is pretty high like aluminum, so it may make less of a difference. But then, heat may soften the hardened grease to help. I might try it when all the other options are exhausted.
If you have gotten a bit of motion, using plenty of PB Blaster and working it back and forth should gradually free it up.
It always amazes me how the parts that seem so simple end up eating the most time...and that there are always more of those "simple" time consumers near the end of a restoration?!?
If you have gotten a bit of motion, using plenty of PB Blaster and working it back and forth should gradually free it up.
It always amazes me how the parts that seem so simple end up eating the most time...and that there are always more of those "simple" time consumers near the end of a restoration?!?