Power Window Motor Differences / Fix?

[markhoward]

I have a late production 78 911sc Coupe and am in the process of replacing a bad window regulator and motor. I purchased both items used from a well known source but found that the motor is different than the original one off the car. This car has the original parallel arm regulator and not the later one that is often retrofitted to earlier cars. The window motor is somewhat larger than the replacement and has a plastic cover over the motor. I would not be concerned about the physical differences except that the three mounting ears on the original motor stand taller than the replacement. The replacement therefore causes the regulator gear to bind against the plastic friction pads if you attempt to bolt the motor down fully.

Is anyone familiar with the differences between motors? The Dansk replacement ones that are available look just like the replacement one I got so think that a new motor would not solve my issue.

The reason I am replacing the motor is because one of the mounting ears broke off. I think the ear can be brazed back one but in order to do that, I need to disassemble the the gear assembly so the plastic parts do not melt. Has anyone disassembled one of these? I cannot see how it comes apart. Thanks!

[WMichelsen]

Your replacement appears just like the original Porsche one I removed from my '87, which has the scissor style regulator.

If all else works, could you add 5mm spacers (or the thickness you need)? Just a thought if you can't return it.

[markhoward]

Thanks for the response. Might go down the route of spacers if needed. I was able to get the original one apart. The metal wheel which attaches to the output shaft is staked in place. I was able to get it apart in the vice. Fingers crossed that it will go back together. Here is a photo of all the guts in case anyone needs a reference. I will try to repair the broken ear either by brazing or maybe see if my friend can tig it. I can serve as a backup if I end up with another motor.

[PeteKz]

I have this pair of window lifts out of a 1979 930 with only 26,000 miles. If you give up on trying to repair yours, let me know if you are interested.