Gearbox assembly problem

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I am in the process of assembling my gearbox using the complete rebuild kit from RGM. When I go to install the inner cover, it will not seat because the 1st gear main sticks out too far. The new sleeve gear bearing is all the way seated. I have disassembled and reassembled half a dozen times with the same results. I am using my service manual and the oldbritts site. Any ideas why the mainshaft won't seat all the way? I added a picture of the 1st gear sticking out and a pic of the new sleeve gear bearing. Thanks, Josh
Gearbox assembly problem

Gearbox assembly problem
 
Are the selector forks back to back on the spindle?
Did you start assembly with the cam plate in the neutral position?
Are the selector fork studs properly seated and in the correct position in the camplate?
 
Josh, it is better to remove the seal from the inside of your sleeve gear bearing. This has nothing to do with the problem that you discribe, but lubrication of this bearing will be improved when this seal is removed.
 
The are 2 sides to the debate on the seals, by retaining the inner seals you are keeping gearbox debris out of the bearing. On the fence on this one but no-one seems to report suffer premature bearing failure which ever method is used so as you bearing is in place then leave it be.
 
Make sure 2nd gear is not overhanging the shaft dia. where 1st fits. If it's not then maybe 1st isn't seating fully on the shaft due to tight splines. I had to ease mine a few years ago to get it to seat fully. That was Andover gear not RGM who make their own I believe? Check the cam and selector positions again to assure yourself they are not the reason and as 2nd main doesn't move, as long as its seated that should not be the issue.
 
maybe the fork isn't on the carrier when you slide it on, so it's acting like a spacer and making your gear stack too wide...

Why don't you just forget installing the shift forks for a moment and do a mock up without them to see if the gear stack is correct without them. That could indicate where your problem lies....
 
Keith1069 said:
Make sure 2nd gear is not overhanging the shaft dia. where 1st fits. If it's not then maybe 1st isn't seating fully on the shaft due to tight splines. I had to ease mine a few years ago to get it to seat fully.

I had the same problem with the new bearing. It was a tight fit over the main shaft where the spline machining stops. I used a plastic mallet lightly to get it seated fully. I think a tiny ridge gets created over time from fettling. Once I got past the tight spot it slid into position nicely. Alternately you could polish it with some ultra fine emery. Did you test fit the bearing when the main shaft was out of the case?
 
Make sure 2nd gear mainshaft is not reversed, it is a very common mistake.
Mike B.
 
I will try all these tonight. Actually the picture shows it assembled without the selector fork, so I know that isn't the problem. I assembled it in 4th gear(and 3rd to get selector forks engaged) on previous attempts. I did use a rubber mallet to make sure that the sleeve gear was all the way seated. I will update after I try these things and see if I get it solved. Thanks, Josh
 
Mike B said:
Make sure 2nd gear mainshaft is not reversed, it is a very common mistake.

Yes makes sure the 2nd gear mainshaft isn't around the wrong way, a very easy mistake to do, wrong way around and your case won't go together.

Ashley
 
The 2nd gear dogs would be facing the wrong direction. That would be pretty obvious wouldn't it?

Gearbox assembly problem


Your main shaft 1st gear splines should be flush. If not you've got a gear reversed. Otherwise main shaft not fully seated.

Gearbox assembly problem
 
Just found my problem. When I disassembled the box awhile ago, I must have put the sleeve gear seal spacer on the sleeve gear. It embedded itself to the sleeve gear, so it looked like it belonged there and I didn't notice it. I am an idiot! Hope I didn't waste too much of your time. About the main bearing, is the concensus to leave the shield on it? If not, is it easily removable? Thanks all and sorry, Josh.

Here's my problem

Gearbox assembly problem
 
I'd remove the inner seal. The sleeve bearing I got from Old Britt's had the seal removed on one side. Yeah, it would probably be fine all sealed-up but I like the idea of a large amount of gear lube constantly being splashed into the bearing instead of a microscopic amount of grease being recirculated inside the bearing. I think it carries heat away from the bearing better too. Some will argue that swarf from the trans will get inside the bearing but anything harmful should settle to the bottom sump of the gearbox. Besides, if you have bits of metal floating around inside your gearbox you have bigger problems.
 
Bowtoy70 said:
Just found my problem. When I disassembled the box awhile ago, I must have put the sleeve gear seal spacer on the sleeve gear. It embedded itself to the sleeve gear, so it looked like it belonged there and I didn't notice it. I am an idiot! Hope I didn't waste too much of your time. About the main bearing, is the concensus to leave the shield on it? If not, is it easily removable? Thanks all and sorry, Josh.

Here's my problem

Gearbox assembly problem
no you are not an idiot you just made a silly mistake thats all we all do it!,with regards to the seal i would leave it on, the lubricant in the sealed bearing is sufficient for the life of the bearing cheers
 
For what's it's worth I just pulled the seal out on one I just redid. Figure if it worked as it came from the factory why experiment.
 
this of course is my opinion and what i do with my engines ,from experience with tuned BSA b44s and advice from a race tuner ,its a bit like running rings in dry or soaking gaskets in oil etc etc
 
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