cgarcer

One of my power windows will not go down. How can I manually lower it on a 77? Door panels are already removed.

F22

You cannot lower a C3 power window manually. You can try to force it, but I guarantee you will seriously damage something there. Does the electric motor still work? Can you hear it when you push the switch? If it still works and it's trying to move, you might be able to help it, but be careful.

If it's actually working, your best bet is to thoroughly clean all the tracks and rollers, as that grease is 38 years old and rock hard. You still need to do this, to both doors, regardless, because rock-hard, gummed up tracks and rollers are the leading cause of Power Window Motor Death or PWMD, a serious condition that has a lot of bad side effects (mainly on you!).

Electrical or Mechanical is what you're going to investigate.

Easy Mike

Did you test the switch?

mysixtynine

Have someone hold the window up (add some up pressure to it) and remove the 3 bolts holding the motor to the regulator.

Remove the motor and the gear and the window should move now.

BKbroiler

Easy Mike

That can be dangerous. Watch your fingers if that door glass drops.

BKbroiler

Thinking a little further on this - the spring in the window regulator will hold the window up and will create more resistance the more the window is pushed down (with the motor removed). Right?

68/70Vette

I was a few months ago planning upon replacing my door windows and the power windows "regulators." There are YouTube videos that are helpful.

I now have all new door window glass and windshield glass in my 68.
Windshield glass is NOS and window glass is OEM Pilkerington Classics. Pilkerington now owns the Libby Owens Ford logo that's on C3's.