Rear window roller repair

[Layne]

The problem: There's a small plastic roller on each window regulator that snaps onto a steel pivot ball thing and rolls inside a track that is part of the regulator. These rollers tend to either break in half, or crack and won't stay on the ball. It's usually only a problem on the rear, I guess the leverage is different or something. BMW doesn't sell the roller alone, you have to buy a whole regulator for $90-ish. This is such a problem that they made a 'repair kit' back in the day that's pretty much exactly like what we're building in this thread, but unfortunately it's NLA.

I found these closet door rollers at Lowe's that looked like they would work (like a year ago) and I finally confirmed that they do. It's a pretty easy process, but you need to be able to drill and thread a hole through the axle for the roller. I did this easily with a lathe, but not everyone has one of those. You could probably do it with a drill press and vice, and maybe with a hand drill if you're careful. Straightness is helpful, but not critical.

Buy some of these. They don't seem to have a brand name, but they're 1" diameter and came from Lowe's. If yours are not identical, adapt as necessary. 1" is probably pretty standard.



Grind off the protrusion from the back of the bracket as smooth and flush as possible.



Drive out the axle you just ground off.



Not shown: This is where you need to drill through and tap the axle. I used 8-32 threads.

Cut off the ball where the old roller went. I used a Dremel tool and it just took a few seconds.



Drill out the hole to fix the axle of your new roller, mine are 7mm.



Then install the roller with the screw from the back. I used button head cap screws. Don't do it like the picture though, the wheel has to be in the track when you install it. You can't get it in if it's already on the arm. At this point you'll see that the roller is slightly too thick to fit into the track. About 10 seconds holding it against a belt sander fixed that right up. Just sand until it fits.



There's no way to hold the axle still to get the screw real tight, so probably best to put some loc-tite on the threads so it doesn't fall out later.

[Binjammin]

Weird, never seen a broken one.

Nice fix though, should be made a DIY.

[sse34]

Had mine break on my window and replaced the whole regulator ... Nice fix i like it a lot

my other window is starting to act up and my try this out

[priler]

ha ha,that's pretty awesome. love it.

[BMW IDFR]

that's what i call fixin! good!