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Old 09-10-2008, 12:46 PM   #1
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Default 6 Speed Rebuild Questions

So as fate would have it, a 6 speed of questionable integrity has found its way into Abe's hookah-lounge and engine rebuild station.

The tranny was cheap since it 'sometimes didn't go into reverse'. When I first tried it on the floor, it felt smooth! Then we tried running it with a drill motor (300 rpm?) and after a couple shifts, yep, wouldn't go into reverse, 5th, and maybe 6th. And I'd heard from the original owner that 3rd/4th are sometimes hard to get into?

I got it all apart (wow it took some beatings to accomplish - hint for future generations, tap each shaft alternating, not one then the other as the book suggests), and things (at a glance) looked quite well - synchros look decent, no broken teeth, shavings. Other than oil being a BIT silvery, it was ok for something which came out of a race car.

Biggest obvious problem: The sleeve bearings in the 5th/Reverse shift fork were in wrong! One was obviously backed out half way, could cause interference. The other was actually loose, and could slide in part way, or could 'fall' out along the guiding shaft, preventing the fork from sliding over into gear.

1) Could I just clean and press in these bearings in 5th/reverse fork? How do I tell if they will stay in?
2) The 3rd/4th fork has bearings only on one shaft of the two which pass through it. Is this right, or do I need those sleeve inserts there as well? They are not sold separately I believe.
3) Are the sensors the same between my NB 5 speed and this 6 speed? The tranny came without anything having a wire on it! I have a new speedo gear, but nothing else, would like to know if I can reuse my reverse and neutral sensors.
4) Can I clean the tranny without rusting it? How?

Thanks everyone! This is kinda a big job, but fun. With any luck, I should have one very sweet tranny when I'm done.
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Old 09-10-2008, 12:55 PM   #2
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4) Mix a little oil with some mineral spirts. That will clean and keep parts from rusting for a while. Or just use mineral spirits and then fill it up with oil.
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