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TR6 Gearbox rebuild issues

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Ribbs

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I pulled the gearbox on my 1973 TR6 with the intention of replacing seals and gaskets, as well wanting to degrease the exterior and inspect synchro's, etc. I've now run into several issues;
(1) Trying to remove the rear extension housing but the rear bearing seems to be seized on the main shaft. Is that common? Any advise on getting it off?
(2) I removed the top cover and got the three selector shafts out to give the brass (?) selectors a good cleaning. I may regret that because now that I look, the three spring loaded detents don't have a screw on cap - they're covered with plugs (like tiny freeze plugs). I seriously doubt that I can get the detent balls back in place without removing the plug and springs. Moss and TRF don't reference these plugs (or bucket type plug, as Moss lists them) and my Robert Bentley shop manual doesn't even mention these - only screw in type plugs. Is there somewhere else to source these?
(3) Once I had the top cover fully disassembled, I ended up with not one, but two, identical small pins. I know that one is called the interlock plunger by Bentley and goes in the 3rd/4th selector shaft, between the two interlock balls. For the life of me, I have no idea where the second one goes. I hate ending up with extra parts left over!!
 
First, make sure you removed the speedo gear. It will lock the tailhousing if you didn’t. Then, it usually requires a press to remove all of the bearings from the shafts. I bought a $100 press 20 years ago that is invaluable for many projects. Without the press it takes a special tool.

Drill out the plugs and tap the holes for the screw in type shift detent spring retainers.

Is it possible the extra rod came out of the reverse detent? The forward gears use balls, but reverse usually has a pin with a pointed end.
 
I built two TR4 transmissions last summer and both had the bearing froze to the mainshaft. I built a puller similiar to what they show on the Buckeye site but it was not enough. The shaft(s) had to be pressed out. Other than that the Buckeye site was helpful for me. Should be the same on your TR6 but there is a pin on the reverse shaft as John pointed out. Make sure you replace the "O" ring seals (3) while you are in there. Bruce
 
Thanks all for the comments. I forgot about Buckeye as a good resouce for this. I sprayed the stuck flange with WD40 today and tomorrow plan to fabricate a puller along the lines of the Buckeye example. Regarding the extra pin, I don't think it came from the reverse detent as I can look into the shaft holes and see the pointed cone shaped spacer is still in there, along with springs visable in the 1st/2nd and 3rd/top holes. As mentioned, it's the exact same size as the spacer between the two interlock balls. No diagrams show anything like it elsewhere. Weird.
 
Ribbs said:
Thanks all for the comments. I forgot about Buckeye as a good resouce for this. I sprayed the stuck flange with WD40 today and tomorrow plan to fabricate a puller along the lines of the Buckeye example. Regarding the extra pin, I don't think it came from the reverse detent as I can look into the shaft holes and see the pointed cone shaped spacer is still in there, along with springs visable in the 1st/2nd and 3rd/top holes. As mentioned, it's the exact same size as the spacer between the two interlock balls. No diagrams show anything like it elsewhere. Weird.
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Spraying Weaselpee on the interference fit bearing and shaft is going to do zero good. Of course, taking it next to a shop and using a 60-ton press to finally get it apart, everyone will think the WeaselPee did it.
 
Its been a kind of crappy day. Thank you for a good laugh!!! First time I have heard it called weaselpee. Be careful, You might get weaselpee on you when the 60 ton press pops it loose.
 
titanic said:
I think the answer to the extra pin mystery in in this article (also from Buckeye) in overhauling the top cover. It describes an extra pin in later top covers. Page 4/7, I think. https://static1.squarespace.com/sta...de40001aacd9b/1560384913595/Gearbox+Cover.pdf
Berry
Click to expand...

Thank you Berry - that answers that mystery! So the extra pin activates the neutral switch.

TOC said:
Spraying Weaselpee on the interference fit bearing and shaft is going to do zero good. Of course, taking it next to a shop and using a 60-ton press to finally get it apart, everyone will think the WeaselPee did it. ​
Click to expand...

That's good - I never heard it called Weaselpee either! I'd love to use a press on this but there's no good way to support the housing when pressing on the main shaft. I think I'll have to come up with something similar to the homemade puller shown in the Buckeye document.
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