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TR4/4A Odd TR4 transmission question

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J

Jerry

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After two hours of work, finally got the countershaft and the gears that rotate on the shaft. The front bearing assembly appeared to have been installed incorrectly. It stuck out more than a 1/16 of an inch and ground into the thrust washer (848660), creating a lip that did not allow the thrust washer to slide out. The lip of the bearing assembly was worn away and the needle bearings free to roam with the countershaft removed. The thrust washer at the other end (848-650) was also damaged, and looked like metal particles had damaged it. So here is the questions:
1. The bearings are stamped USA on the them which seems strange for a british tranny unless this unit had been rebuilt. The owner bought the car in 1970 so it could have been rebuilt or did they really buy bearings from the USA?
2. The rear bearing assembly has not come out yet. My puller does not seem to grab onto something. What kind of puller do you use for this bearing?

Jerry
 
1. Likely a rebuild, which also explains the bearing not being far enough in.

2. It's been a long time, but as I recall I wound up taking those bearings out in pieces. The outer shell was so brittle that it broke instead of sliding, so I just kept breaking pieces until it came loose.
 
I did not try breaking it into pieces. I tried two different pilot bearing pullers and a slide hammer. No success. So maybe a chisel may work. thanks

Jerry
 
It sounds to me that the cluster gear may not have not dropped to the bottom of the case allowing you to then remove the main shaft. If it has not dropped the mainshaft and gears will hit the countershaft. First confirm that it has dropped. Remove the circlip from the mainshaft but leave the large retaining clip on the OD of the bearing. Then turn the case upright and lightly tap on the end of the mainshaft driving it off the bearing. PROTECT THE END OF THE MAINSHAFT WHEN DOING THIS. Once the mainshaft is driven out of the bearing then gently tap the bearing out of the case and Bob's your Uncle.
I don't understand how the front bearing could have been off by 1/16 unless the circlip was never installed but if it was then how was the front cover able to be securely fastened to the case.
 
Possibly I misunderstood, JerryVV, but I thought he was talking about the roller bearings inside the countershaft gear cluster; not the ball bearings on the main and input shafts.
 
Yep, problem with th caged roller bearings. We got the old ones out, and now to put it all back together. By the way, a good use for an Ipad or laptop is following the instructions on a rebuild.
Jerry
 
I misread his problem and thought it was the mainshaft bearings. What is puzzling however is how did the bearing migrate. The only explaination that I could think of was a prior transmission problem where the caged bearing ruined the bore and someone stuck one in a loose bore slapped it together and moved it on to someone else. The caged bearings are a press fit into the Countershaft gear bores. Tough to remove too.

I'd look for a new or good used Countershaft Gear at this point. Would not use that one again.

Sorry for the confusion on my part.

These were originally Torrington bearings and could not be sourced via a local bearing suplier, only through Triumph. I tried when I did my first gearbox in 1970. So the Made in USA that you have (had) must have been the wrong size. As I recall it was the OD that was an odd size.
 
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That means that someone had this transmission apart before. And they did not install the bearing correctly or it moved as you suggested. But since they were so hard to remove, I bet they did not install it correctly. As of 3PM today, all the gears are back into the case. Just have to finish up the seals on the ends and the throw out bushings. Gears looked very good. The syncros were worn, the new ones suppied by Quantum are very tight.
Jerry
 
But if your are really crazy enough to re-build a tr4/6 box why not retro the hand packed tr3 style
rollers for extra durability??? It only takes another hour and 4 beers,a dummy counter shaft, some grease......
MD(mad dog)
 
I've never found the TR3 rollers to be a problem to install, and never needed a dummy counter shaft. Just use plenty of the grease you mentioned and use the counter shaft itself to set the rollers in place before assembly. Very rarely will they upset when installing the shaft, and it's apparent when that happens. Then it's time for that other beer.
 
Isn't the bore different for the bare rollers? ISTR it had to be larger to fit the caged bearings (which gave a way to "repair" damaged countershafts).

Or you could follow Bob Schaller's suggestion and go all the way back to bronze bushings. Slightly more friction, but only in lower gears, and should last forever if the oil is clean.
 
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