Getting a sunroof and wiper motor rebuilt rather than replacing?

M

mandala

Active Member
Messages
64
Reaction score
0
Location
Portland OR
Hey gang,
Trying to get my 74 E9 out of the shop so trying to get the last of the parts that I need. They are saying I need to replace the sunroof and wiper motor. After endlessly searching the Internet for them the idea came that I could probably get them rebuilt locally instead of trying to find used motors from parts cars. Has anyone done this? I am pretty clueless with electronics so forgive me if this is an obvious question. The weather is finally getting nice here in Portland and I want to get my cs out not he road!
Thanks for any info you all have!
Jeff in PDX
74 3.0cs
01 M Coupe
 
Rebuilding motors used to be the standard way of getting your car back on the road. Local shops had the supplies, brushes, bearings, armature wire, etc. and would fix you up. An option was to get an exchanged rebuilt part which was more expensive but faster and so local shops did less and less rebuilding work.

Now we are having trouble getting quality rebuilds, even from name brand makers as it's done in far away places with little care for the quality of the work. So it's back to getting our cores rebuilt if we can find a shop with experience and parts to do the job. Fortunately, electric motors are pretty simple and the basic components are durable and don't deteriorate sitting on a shelf so there's hope there. Bosch is well enough known that you shouldn't have too much trouble finding a shop to take care of your needs unless, of course, your motors have suffered a severe failure such as fire, flood, or impact.

Sometimes the brush contacts on the armature (the spinning part) are badly worn. Light wear can be cleaned up, but sometimes they wear out and the armature will have to be rewound. This is beyond some shops but if the part is valuable enough, it can be done. It's more often done for large industrial motors because of the cost of new ones vs the cost of repair, but when you can't get a replacement motor, sometimes you gotta pay the man.

There's a youtube video for just about anything, but the quality varies quite a lot. Here are two videos of wiper motor repair by amateurs just so you can see what is involved. It helps to understand what your shop might say when looking at repairing yours.

 
You never mentioned what is wrong with each.

When you think of the poor availability and cost of replacement, rebuild is logical. Sadly rare to find someone who rebuilds electric motors for a living. You may want to venture to repair yourself as these things are nothing more than an (intact) armature, some bearings and motor brushes.
 
Yea they did not specify what was wrong with them. The sunroom motor is original as far as I can tell as I have not replied it in the 17 years I have owned it. The wiper one I did replace with a rebuilt one probably about 12 years ago. Thanks of the information!
 
mandala said:
Yea they did not specify what was wrong with them. The sunroom motor is original as far as I can tell as I have not replied it in the 17 years I have owned it. The wiper one I did replace with a rebuilt one probably about 12 years ago. Thanks of the information!
Click to expand...
Brushes are the first things to go. When they wear down, contact with the armature becomes poor and the motor has low power or won't work at all. Grease can harden with time making even good motors run slowly and pull more current, enough to blow fuses. Both of these issues are simple to resolve, just taking some time, and well, the correct brushes, but they are carbon and should be available.
 
Re the wiper motor, if you remove it and bench test it you'll find out whether any problem might lie with the motor, or the "transmission" which has something like a 47:1 reduction ratio. I've had 'em apart, it's not hard if you are cleaning, regreasing and reinstalling.

Odd failure: wife's '84 Volvo diesel wipers started grinding. Took out the motor and discovered the magnets had come unglued from the casing. Some acetone, some epoxy, alles gut! or however it sounds in Swedish.

E3 motors can be used in E9s I believe, someone correct if not so. You could check me while sitting at your desk: look up the part number for both E3 and E9. Same number would indicate identical motors; differing numbers suggest some slight difference, maybe only the terminal assignments on the plug.
 
Thanks for all the great info! I am having my shop take out the two motors and hopefully I can find some "old timer" here in Portland to rebuild them. If any one has knowledge of someone in Portland let me know! I guess worse case scenario is I have to ship them to someone to get done. Any suggestions for that ?

I love this site for all the greta info you collectively have!

Jeff In PDX
74 3.0CS
01 M Coupe
 
I wonder if the guy that @HB Chris uses to rewind alternators would take a look.

I’ve read from other members that the grease in both turns to concrete. You may just want to clean and degrease before sending them off.

If you look at the sunroof motor, it is just the same sardine can motor as the windows. You might see if you can use an e28 window or sunroof motor.
 
Can’t use e28 as the sardine can drives a cable to the separate gear housing in roof. I agree about wiper motor, the contacts get all gummed up, very easy to remove cover and clean to see if that works.
 
CBF745C7-B98A-4F41-B085-3E9691BD65B2.jpeg

Jeff. I think the motor on the right is the one you need and I have it. the forum can likely confirm if it is the correct one. I took the cable as you can see but can forward the motor.
 
I have had my left front window motor rebuilt. But it was many years ago. "Auto electric" shop would take on anything. Once he had the motor apart, he realized he would need to order parts from Germany, so some delay. I didn't care. What I did appreciate is that he wanted to get this right. And once the parts arrived, his repair has held up, been 12 years. So, I still have original unit attached to my car, and it functions as new. Seems it is getting more difficult to find shops that will care enough to investigate and research and order in parts for a proper fix. Hope you can get yours back in service.
 
You must log in or register to reply here.
Back
Top