C1 Powerglide Kickdown

[Jimmy J.]

I still cannot get my 1959 powerglide to go into passing gear when floor it. I have reset the linkage using the corvette service manual. Does anyone have any ideas on how to get it working? Thanks in advance. Jimmy

[Jack H.]

At what speed are you trying? *NM*

[Gary C.]

Re: C1 Powerglide Kickdown

Jimmy

I had similiar issues with my powerglide in the 63. I think you will find that if you get the linkage adjusted properly it will shift as it should.

IF the linkage is adjusted according to the manual or AIM and it does not downshift, use that as a starting point and adjust the transmission rod at the carburator several turns (I forget which direction) and try it again, if it does not downshift, turn the adjustment several turns past your initial starting point back the other direction. IIFC on my 63 the shorter the rod the sooner it will downshift, but I could have it backwards. It will downshift when the lever on the transmission is deflected fully against the internal stop. The adjustment allows this to occur sooner when you "step on it" or can be adjusted such that the lever never bottoms out and hence it will not shift.

Hope this is of help

[Michael H.]

Re: C1 Powerglide Kickdown

Jimmy,

Gary has it right. Shortening the trans control/downshift rod will do two things. It will raise the 1-2 upshift MPH point on normal acceleration and it will also enable the forced downshift if it's not functioning now. Go a few turns and test. You may wind up shortening this rod several turns.

If you still have no passing gear, there is a possibility that the two stage TV in the control body had been adjusted incorrectly. With the TV (downshift) linkage disconnected completely from the carburetor, you should be able to feel spring resistance if you pull on the rod. Near the end of it's travel, there will be a 2nd spring that is activated and that's the spring that controls the TV valve itself.

Try the linkage adjustments first and see what happens. If still no passing gear, we'll go from there.

If the rod is currently too long, you are most likely experiencing a very early 1-2 upshift also, no matter what throttle opening at the time. This would be an indication of incorrect rod adjustment.

Michael

[Jimmy J.]

Kicking Down at 35 to 55 MPH *NM*

[Jimmy J.]

Re: C1 Powerglide Kickdown

THANKS GARY, MICHAEL that fixed it working like it should. Jimmy

[Dave Suesz]