Transmission won't shift into 3/4

[MonzaDave]

Background -- It's a '65 4 speed that I had a guy who has a good reputation with manual transmissions rebuild (bearings, blocker rings, etc.)

Situation -- I reinstalled the drivetrain in the car without checking the transmission for proper operation.

Problem -- I can't get the tranny into 3 or 4. It's not the linkage --the problem persists with the linkage disconnected. Getting reverse after going through the strong detent is no problem. First and second, again, no problem. But I can't rotate the shift rod into the third and fourth gear position. It just goes a wee bit to the left and stops solid. Someone suggested that one of the shifter forks could be installed backwards.

Next -- Tranny fluid is draining and I'll remove the side cover. If that doesn't uncover the problem, the tranny is coming out and going back to the rebuilder.

Question -- Any guesses?

[bbodie52]

I've never rebuilt a manual transmission, so I can't rely on past experience to suggest anything.

Maybe the attached Overhauling the 1961 Corvair 4-speed Transmission guide will help you to spot the problem, since it contains a lot of detailed illustrations and pictures. But I would be surprised if it can be corrected without removing the transmission and dismantling it again, unfortunately. The 1961 guide should still apply to your 1965, since the transmission design did not change until 1966. I have also attached the appropriate section from the 1965 Corvair Chassis Shop Manual. Hope this helps!

[Phil Dally]

Removing the side cover might void your warranty.

Just take it back...it's an internal problem.

[MonzaDave]

Here is a picture with the side cover removed. The transmission is in neutral. The 1/2 shift fork appears to be positioned correctly (1/2 works fine as well as reverse), but the 3/4 fork is displaced the right. It's not solidly locked in that position because I can move it a smidge (a few ten-thousands probably). The shifter shaft can't be rotated far enough to allow the 3/4 fork to move. I can't see far enough down into the tranny to see what might be going on with the shifter shaft, but the tranny needs to come out anyway. No worry on the warrantee -- there was none and the work was done over a year ago.