Grab the driveshaft and turn it, while watching the governor. It should turn. It's possible the gear isn't meshing with the output shaft for some reason.

If you remove the valve body, be careful- - - -the gaskets are easy to damage, and there are several check balls that will try to fall out and roll away if you don't hold the valve body perfectly level as you lower it.

I just remembered another possible problem. There's a snap ring about the middle of the transmission case that can jump out of place the first time a 1-2 shift is made, if it happens to get mixed up with another, similar-sized ring during reassembly. After that, the trans will not upshift out of 1st. speed. One ring has a tapered face- - - -the other one is square-cut. If the tapered ring is installed in the case instead of where it belongs, it won't stay put.

Please don't ask me how I know that- - - -or why it took two tries for the lesson to stick!
LOL!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!