Hi,
I am trying to figure out what the rubber o-ring on the main shaft's purpose is. Also, is it located in front, or behind the large main shaft bearing? The manual (schematic) does not show it, and the manual just says "main shaft large tapered bearing and o-ring". Has anyone come across this before? Thanks for any advice!!
Mike

 

Purpose? I dunno. It's got a groove cut in the mainshaft for it tho. Perhaps it's to hold the front section components on the mainshaft during pre-assembly at the factory (while they move them around). Or it's a "placeholder" - if you don't hit the o-ring on the mark, then you screwed up assembling something in the lower part of the trans.

I've never put one back together without the o-ring, so I don't know what would happen if you didn't.

 

Is it the groove behind the bearing, or in front of the bearing? Thanks for your help!
Mike

 

If you have the transmission face-down on the bench, the O-ring is located on top (above) the bearing. The o-ring goes between the bearing and the 5-6 driven gear (which is the press fit gear that goes on the mainshaft after you put the main case on).