Well, looks like I just got the 'Bird running again only to chase the gremlin into another part of the car... Now the passenger side power window is not lowering properly. Searched the forum and saw some discussions on the topic of replacing the motor, but I'm not convinced I need to do that; the motor seems to be working properly, but the window just stops moving... Reasons abound in other threads for a stoppage in window movement, but I'm coming at it a bit blind at the moment, so perhaps someone can focus my attention a bit better if I just describe what's happening in my case...?

When commanded, it will go down properly for about the first 3 inches, then it stops and something (presumably a gear or other mechanical linkage) makes a chattering noise. If I then command it to go up, the window will immediately return to the fully "UP" position (although it now seems to jam into the T-top pretty hard if I'm not careful -- like something's gotten out of adjustment). The window does not appear to be out of alignment (like it's come out of the track), but...?

Any ideas, suggestions, etc.? I figure I'll need to pull the panel off the door to investigate, so any suggestions to ease that job or warnings about potential pitfalls are also appreciated.

 

Clean and grease the power window tracks. You could have something in it or a dry spot causing it to bind.

 

That's a very likely possibility, given the age of the vehicle and lack of use over the past couple of years. Thanks!

 

Sounds like the roller on the regulator is hitting something caught in the track.Causing the chattering sound.Less likely, stripped tooth/teeth on the gear drive.

 

I'm leaning in the direction away from stripped teeth as well. I've tried to gently 'encourage' the window to go downward, and it seems more like something is binding rather than just a gear or cog slipping. I'll need to investigate further though.

 

Well, I got the chance to look into this a bit further this weekend. I finaly got the door panel off (another story there... ), peeled back the vapor barrier, and was able to observe the inner workings of the door/window.

It appears that nothing is binding in the window mechanism. The chattering noise is definitely coming from the area of the motor. The window can be cajoled into going all the way up/down, but it required me to pull/push on the glass to get it past the point where it is stopping. Looks like the motor gearing has some broken cog(s)...

From what I was able to see using a mirror, the external plastic cog on the motor (the one that engages the long 'blade' running the scissor jack mechanism connected to the window pane) is fine/intact. Where do these cogs usually fail? I mean, is it usually something external to the motor that can be replaced without removing the motor; or is it something internal to the motor itself?

 

Probably a worm gear drive inside the window regulator using a metal worm on a plastic gear. The fact that you can push it past the stop spot says you probably need a new regulator (motor) as i think it is a sealed unit. To replace it you need to move the window tothe half up position and jamb it with some rubber wedges, remove the rear guide, then drive out the center pins of the regulator rivets, then drill out the rivets with a 1/4" drill. Then remove the regulator. If you want to take apart the regulator the sector gear must be locked in position because it is under spring tension which could cause an injury when it lets go.
Drill a hole through the regulator sector gear and
backplate and install a bolt and nut to lock sector
gear in position

 

Or do it the easy way drilling the holes in the inner door skin. This is standard procedure on most GM cars and G-bodies even come with dimples stamped in the skin to locate where to drill.

 

The regulator is less than $30. I wouldn't mess with it.

 

Thanks! Yeah, that was what I was afraid of -- something worn that was not easily accessible... Typical...

Yeah, I'm not keen on drilling or cutting holes where they don't belong on this particular vehicle. I'm trying to keep it as 'unmolested' as possible, even when making necessary repairs.

Well, that's certainly good to hear! What's the source on that part?

I will probably need to replace the vapor barrier too. The one I pulled back doesn't stick very well any more... I suppose I could tape it back up, but I'd feel better about the job if I just did it correctly...

 

The next step in the saga is going slowly. I'm a bit stumped about how all that hardware inside the door can be removed... It looks to me like it was all put in there before the door 'halves' were spot welded together, and the access holes are barely big enough to get a hand or mirror in, let alone extract the regulator and/or motor... Any guidance...?

I've been warned about ensuring the window is properly positioned to relieve spring tension on the motor before working on this, but I've gotten conflicting information about which position is correct. If someone could clarify that better for me, I'd appreciate it.

Still also seeking some guidance on replacement parts (e.g., vapor barrier).

 

The spring is there to assist in raising the window. When the window is at it's highest position, you have as much of the tension relieved as possible. You may have to move the position of the regulator arm after taking it loose to squeeze it out of the opening in the door IIRC. (hook the wires up and work it with the switch). But I assure you you can take it out with the door on the car and in one whole piece.

 

OK, thanks! The fully "UP" position is what I was told by another trusted source, so I'll be sure to go with that.

Good to know. But I'll have to take your word on it for the moment...!

 

Allow me to wake up this old thread for just a moment. Where did you source a new regulator. I actually need 4 of them, but I can't seem to find new ones.

 

I did this a couple months ago. If I remember correctly there are some 10mm bolts that hold the regulator to the inner door and some large aluminum rivets that will need drilled out on the motor housing to door. Once you free the regulator from the door you should be able to slide the rollers off their tracks and collapse the regulator and slide it out of the door from the rear.

It's a worse job than pulling an engine in my opinion. For the sake of my sanity.... If I ever have to do window motors again it again, I will most certainly do the hole drilling method.

 

OK. Just to follow-up on my situation and progress:

After hearing what a pain this job can be (both figuratively and literally), I decided to engage some [retired] professional help to get this repair done. Ultimately, the culprit was the motor. After a quick trip to O'Reilly's to get a replacement motor, the window works perfectly again!

Thanks to all who provided guidance!