Topic: Bad power window motors

[marx3]

The windows never ran great on the 78 I am restoring. They have been able to go all the way up bad all the way down by them selves. Slowly but they made it.
Now I got the car back from the painters and the passenger side will go up but that's the only movement the windows will do on their own.
If I supply the motor with a 12v source the motor will move, but still very slowly, almost nit at all.
Are these motor known to be bad at this age? Or are they known to ground bad?
I took the switch apart and renovated it.

[eroc022]

They are known for bad grounds. I think there is a sticky with a new revised way to wire it so it's efficient

[Wallington]

If you have the door trims off, run power and ground direct to the motors, remember the motor cases are ground and plug simply have live feed for up or down. If still slow then its pretty much the motors and window track condition, having bypassed all the wiring relay and switches.

[marx3]

I suspected it was a bad ground when I got the car, since they ran but ran very slowly and both door dinges where worn. I know they both worked before the doors where taken off at the painters. The weird thing is I have tried with a booster, sticking the negative clamp directly onto the doorframe and supplying either feed wires with direct 12 volts.
Could it be the motors got fried in the oven at the painters? Or maybe the booster needs to be charged...

[Wallington]

Wouldn't be hard for the hinges or door pillar mounting area to get a coat or too of paint if the doors have been off and worsen the already bad grounding.

[marx3]

I think you are right.
It's just a little weird that the passenger side will go up but not down...
Anyways, I checked out the thread on adding relays. I am doing this and also adding ground wires to the motors for insurance.

[Angelo]

Resistance adds to this. Make sure the tracks are clean and everything is well lubed. I put new outside felts and rubber seal in my passenger door and it improved my up speed a bit. The relay setup made the most improvement. Having the engine running while using the windows is even better in my case, I have a distribution block that is directly wired to the alternator that my power windows now draw from. Usually down goes faster faster than up but only a touch faster.

Make sure the rivits holding the motor onto the door are not loose, that will mess with the ground as well.

[marx3]

Gotcha. If I detach the glass from the regulator, the glass moves up and down in the track real smooth.
I put 12 volt from a battery on to try each motor and they both ran by themselves this way.
I think they will run better with the engine running.