EDIT: WTB - Front Driver e28 window motor driver side front...

Nachtycoupe

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After a bunch of trouble shooting after window wouldn't roll up it is determined it is the motor. I miss my hand cranks for windows and roof. I think they are referred to as "tuna cans." Looking for one in good shape, good brushes, works, etc.

I also would like to upgrade to e28 motor. I understand there are some mods needed, will worry about that if someone is willing to sell or knows anyone online that sells them. I made some calls and no luck.

But I will take a OEM one as long is it isn't on it's last leg and has been rebuilt or new OEM.

Another idea was to see if an alternator shop or someone like that can rebuild it locally. The brushes are shot. I have it out and need to make calls but not counting on finding anyone local, maybe someone knows a place I can send my original to for rebuild?

Any options or thoughts on what to do I am all ears. Thanks for any help or advice in advance. I'll take all four e28 motors or all four stock motors in case this happens to the other three windows. They are all very slow, including the sunroof but do work and I know that is common. The windows at least seal as they should. But I need that window working as we get random rain here even if none in the forceast due to mountain living. A lot of micro climates around the lake, valleys and passes.
 
Shoot a message to @Koopman he is often able to source these. If you're going through the trouble I would do the upgrade to the faster E28 motor. This is a slightly obnoxious process but completely do-able. It's the first major rebuild thing I started with on my car o these many months ago so it's still relatively fresh in memory, happy to hop on a phone call or facetime to give pointers. The hardest part is the wiring going from the older 3-wire motors to the newer 2-wire motors and adding relays. Not physically hard but it's a bit brain-contorting.
 
Your 74 is already compatible with the e28 motor, you don’t have sardine cans. First clean the steel wheels with ball bearings on the rear track, spray carb cleaner on them. Best is to remove and soak in gasoline. Your town should have an automobile electric repair business that can rebuild an alternator.
 
I think they are referred to as "tuna cans."

That's "sardine cans"! But Chris says that you have a '74, which evidently has the newer style motors. Posting a photo of what you have would clear things up. I have posted a photo of e28 motors below. If by chance your car does have sardine can motors, I wouldn't bother rebuilding them - the newer style motors - whether from a late e9 or an e28 - are the way to go.

Pair of e28 motors.jpg
 
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Your 74 is already compatible with the e28 motor, you don’t have sardine cans. First clean the steel wheels with ball bearings on the rear track, spray carb cleaner on them. Best is to remove and soak in gasoline. Your town should have an automobile electric repair business that can rebuild an alternator.
Thanks Chris. You told me that and with everything going on I completely forgot. Nice to know no extra mods needed. I’m guessing e12 is not compatible. I never hear of that swap.
 
That's "sardine cans"! But Chris says that you have a '74, which evidently has the newer style motors. Posting a photo of what you have would clear things up. I have posted a photo of e28 motors below. If by chance your car does have sardine can motors, I wouldn't bother rebuilding them - the newer style motors - whether from a late e9 or an e28 - are the way to go.

View attachment 220862
Cool thanks Jay. I have everything apart in a box in garage. I’ll post pics tomorrow. Everyone has been very helpful. Thanks guys!
 
I’m guessing e12 is not compatible. I never hear of that swap.
Yes, they have to be e28 motors. And not just any e28 motors - that would be too simple - they have to be REAR e28 motors. And the L rear motor from an e28 goes on the right side of an e9 (either front or rear) and visa versa. The correct motors will have an 8 tooth drive gear; motors from other BMW and Porsche models with 10 tooth gears will otherwise look similar, but not mesh with the large gear on an e9 window regulator.
 
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I searched the forum and saw the question but never the answer as to whether done older Porsche or Mercedes motors with 8 teeth would work. Those are relatively common on eBay and also moderately cheap. Would be a nice alternative
 
Late E9 motors look the same as E28 motors but are about 40% slower. But E28 literally bolt on are already wired correctly.
 
Thanks Rudy...I edited the ad after realizing the '74 is NOT the sardine can motor but still very slow like you mention. I was told the same thing, that it will bolt right on. My question is do I need to swap the regulator too? Or will the e28 motor work with the '74 regulator. Since this sounds like an easy swap, I am now just in search for an e28 drivers side front window motor and regulator (if needed).
 
I am now just in search for an e28 drivers side front window motor and regulator (if needed).
No, you should be in search of an e28 passengers side rear window motor (see my post #7 above). I can't imagine that an e28 rear regulator would fit the front of an e9, so my guess is that the '74 e9 regulator accommodates the mounting pattern of the later-style motors.

e9leveque said:
I searched the forum and saw the question but never the answer as to whether done older Porsche or Mercedes motors with 8 teeth would work.

My guess is that they would. Back when I was looking on ebay for motors, most of the ones I saw for Porsche / Mercedes were 10 tooth. I do recall reading somewhere that certain Porsche 928 models used an 8 tooth motor. Maybe some Mercedes models did as well. So if those cheap/common ebay motors look like the photo in post #4, and have 8 teeth, they'll probably fit.
 
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Thanks Rudy...I edited the ad after realizing the '74 is NOT the sardine can motor but still very slow like you mention. I was told the same thing, that it will bolt right on. My question is do I need to swap the regulator too? Or will the e28 motor work with the '74 regulator. Since this sounds like an easy swap, I am now just in search for an e28 drivers side front window motor and regulator (if needed).
Nope. Regulator is perfect as is. Just clean it beyond clean. I found that the slides needs to be filed as they bound up on the tracks some.
 
Looks like maybe these are more available than I had thought - here’s bmw one for not too much.


And here’s a Mercedes one with 8 teeth. I guess may be worth an experiment at some point. I have my e28 motors installed now but wondering if this would be a viable route as the numbers of these motors dwindles
 
Looks like maybe these are more available than I had thought - here’s bmw one for not too much.


And here’s a Mercedes one with 8 teeth. I guess may be worth an experiment at some point. I have my e28 motors installed now but wondering if this would be a viable route as the numbers of these motors dwindles
 
So the e28 motors are all interchangeable, front back, right left? in this case, the left rear will fit the front driver door motor?
NOPE! I'd phrase it as: "e28 motors are not interchangeable, front back, right left. So, only the right rear e28 motor will fit the e9 left front drivers door".

For what it's worth, right rear e28 motors will also fit the e9 left rear regulators. And visa versa.

With regulators designed for sardine can type motors, some modification to the regulators and wiring is required, which is described in the thread at: https://e9coupe.com/forum/threads/a-few-tips-on-installing-e28-window-motors.27320/

Nachtycoupe said:
Here is a pic of the window motor.

That certainly isn't a "sardine can" -style motor; those have separate gearboxes. Yours looks like the configuration of an e28 rear motor, so something like the one on ebay referenced in e9Leveque's post #13 should fit.
 
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NOPE! I'd phrase it as: "e28 motors are not interchangeable, front back, right left. So, only the left rear e28 motor will fit the e9 right front and right rear regulators."



That certainly isn't a "sardine can" -style motor; those have separate gearboxes. Yours looks like the configuration of an e28 rear motor, so something like the one on ebay referenced in e9Leveque's post #13 should fit.
I was told the motors changed in '74, I believe these are original to the car, but could be wrong. The picture on Ebay looks slightly different than these and these are VERY SLOW and I heard the e28 was a faster motor/regulator. Not sure why BMW would redesign in '74 and still have a slow motor...not like them.
 
I'm just going to grab that Ebay motor so wish me luck. Hopefully it is in working order. I reached out but no word back. Thanks for all your help guys.
 
The picture on Ebay looks slightly different than these
When you say "these", I assume you mean your motor pictured in post #16. It's a little hard for me to tell exactly what that one looks like since it is disassembled. I can say with certainty that it isn't the earlier, "sardine can" style. Does the side of your motor with the gear have the three, 6 mm, tapped mounting holes that the motors shown in post #4 have? If so, a right rear e28 motor should bolt into your left regulator.
 
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