Arrowstorm

I'll give ye the basics. Window has always worked great. No slowing of the motor or anything like that since I got it.

I have noticed in the past once or twice that if I did not shut the tailgate properly, the window wouldn't come back up, so I have had to open and shut it again. I have seen where the door didn't latch all the way and if you try to raise the window then, you get absolutely NOTHING. No clicking, no movement, NOTHING. I know that there is some mechanism that provides a ground to the motor to make it work when the gate is fully closed, and I think that's my problem, but I can't really find it.

Here are the basics:

The power supply to the motor is good. I have 12v from both terminals in the wire harness to the motor from both the dash switch and the rear lock switch.

I was literally taking stuff out of the back when I shut the tailgate, used my key to raise the window and from a totally down position, it just STOPPED midway.

I was wondering if there was a way to supply a ground to the motor itself to see if I can get the window to go up or down.

Or maybe.... if something is up with the door jamb or whatever supplies the ground when the tailgate is in the fully closed position.

At this point, the window is still about 2/3 of the way up, which provides access to the motor and most of the internal parts.

Any help from anyone who knows anything about these power windows would be greatly appreciated.

Thanks,

Buz

pyasher

I am not familiar with the Oldsmobile wagon but I'm sure there's something connected to that latch that prevents the window from operating unless the door is fully closed. I would invest in A repair manual or assembly manual if available which will give you the details on how it works. You could always apply 12 V directly to the motor and catch ground off the body and see if it will go up-and-down bypassing the latch. Good luck!

Yellowstatue

Check the inter-lock switch in the jamb. It prevents the glass from operating if the gate isn't completely closed. Follow wires from motor to jamb switch.

Arrowstorm

Ok, so after supplying ground to the motor thru the jamb and also to the casing itself, I noticed that when I pressed the button for the motor to move, all the lights dimmed int he car, the motor did nothing, and I determined that motor was bad.

So I pulled it out and I have ordered a replacement.

Problem is, the replacement does not come with the gear that moves the regulator teeth.

In the pictures, the greasy one is the motor I took out and the nice clean one is one similar to the motor I got to replace it. So how do I take MY gear out and put it in the new motor?!

Any ideas? I saw a ford guy do a gear replacement on his power window motor and he just pulled it right out. I haven't tried yet on mine, but it doesn't look like it just pulls right out.

oldcutlass

Providing a ground to a power side may have inadvertently applied a short. If you click on the link, here are the wiring diagrams I have for your car.
https://s3.amazonaws.com/ClubExpress...L6xJoemltL4%3D

If the above link does not work click on this one and choose 1972 Chevelle non SS, then scroll down, it lists all GM tailgate window setups.

http://www.peachstatechevelles.com/c...=236&cat_id=-1

I have no clue on how to get the drive out of the motor assy.

Arrowstorm

Nah, I didn't apply a ground to any power source. I have the Chassis service manual and the schematics for the wiring back there. Both leads to the motor are 12v.

I only applied ground to the lock out switch and tried the casing of the motor itself.

Got a new motor coming anyway. I just gotta figure out how to get the gear out of there.

oldcutlass

The lockout switch is a power connection, if you jumper it what happens?

joe_padavano

^^^This. Just pull it out and install in the new motor. The gear can be difficult to pull out due to the seal and grease, but keep at it. It just comes right out.

Octania

Looks to me like the gear comes right out.
you will use all new grease of course and lube the window tracks and rollers.

Arrowstorm

For general reference, because I couldn't find it on the net myself, this is the schematic from my service manual. It's on a CD, so.... I had to take a picture.

Also, when I pulled the motor out, there was no "white"wire connected to it at all. The lockout switch just gets bundled with the power wires (for window and tailgate switch) behind the regulator and I can't really see where it goes.

I suspect that it connects somewhere BEHIND the regulator so that when the door is shut, the jamb completes a ground circuit on the latch and the motor is therefore grounded because it bolts into the regulator itself.

Sound right? Or am I just guessing? Lol

When I get home, I'm gonna have a beer or two and see if I can't pull that gear out of there.

Thanks!

Buz

oldcutlass

Hmmm that diagram is way different than what I had which stated all the different GM types. Ok, if that's what you have you are correct.

joe_padavano

GM has used two different type of power window circuits over the years, one that has separate UP and DOWN windings with a common ground wire and one that simply reverses power to the motor windings with no ground wire. The diagram above is for the latter, obviously.

As for grease, use silicone grease with the plastic gears and window rollers. Petroleum-based grease will attach the plastic parts. Silicone won't.

Arrowstorm

Gear pulled right out. Wasn't expecting that. I grabbed the stud in the middle with some pliers and pulled and it just popped right out.

Added bonus: The gear wheel that spins that middle gear is nothing but plastic and it's in good condition as well.

When I get the new motor, I'll grease it up, install it and hopefully all will be right in the world of this Cruiser.

Arrowstorm

Update: It was the motor.

Got a new motor, but the motor mount studs were a tad too long for the gear to reach the regulator, so I had to cut about 3/4" off all 3 of the mounting studs. After that, though, it fit right in. Plugged everything in, tested the window and it goes up and down faster than ever. Brand new!

Thanks, guys!

Yellowstatue

You must have had a lot of beer...It took you two months to fix

Arrowstorm

Lol. Nah, just took months to get around to posting the conclusion.

You're right about the beer, though. Getting the back panel off when it is stuck in the "window up" position so that opening the tailgate is impossible did require a lot of time, patience and ale...