Electric Window Motor Upgrade

Arde

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Also make sure the switch is "clean" (low resistance). Sometimes it is best to take a switch from the rear window that presumably has seen less use. I assume you'll try it with unloaded motor first (dettached from the window regulator).
 

x_atlas0

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Arde- Excellent work! It functions exactly as it should, as I made a test setup using 2 lantern batteries, attached the ground to the negative pole of the battery, and the 12v to the positive pole.
 

2800cs

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pin numbers

Hello all.

I switiched out the drivers side motor this past weekend...Took more time then I thought. It was a little difficult to remove the window crank assembly.

After I found that little hole on the back so I could remove the final counter sunk bolt holding on the transmission and figured out that you need to remove the tension spring in order to crank the arm all the way down, I got it out.

Anyone know off hand which pin number to ground....Im using the original hot wires...just need to ground the swtich.

Three of the four pins are already used.... Do I just ground the last open pin??? Just want to be sure before I fry something.

:)
 

Malc

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Pictures posted by X-Atlas0 of the motor from an e28 are the same as those used by Saab on the 1978 - 1993 900's front and rear windows
I have a few "in stock", oh dear
Malc
 

2800cs

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Got them in and working!!

Grounding the one open pin on the switch did the job!!!

Windows are only a tiny bit faster, but it never sticks and doesnt need any finger help to get them going!

BTW..for anyone thinking of doing this....light grinding of the inner door will not get these in....you do need to cut a chunk out of it....I used a roto zip blade.
 

x_atlas0

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Hey, Arde, when I did the wiring like this for all the switches, the rear window switches gave me issues. (the ones in the rear armrests) If they were connected like the front ones, the system would ground and I would blow fuses. All the switches work fine when they were not there, however. Suggestions?
 

Arde

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Interesting. The armrest and console switches are presumably wired in parallel. The only way you would short the circuit is if one of the switches (either armrest or console) does not quite open when in the idle position. Could be that it is tired mechanically or has lots of deposits making it conduct (hard to believe). I assume the fuse blows when you operate one of the rear windows, not just by sitting there wired the new way. If that is the case
the bad switch is the one you are not actuating when it blows. (If it blows when you actuate the console rear right window, then the right armrest is bad, if it blows when you actuate the armrest switch, then the console switch is bad).

Pull the suspect switch and measure resistance between all pairs of pins
when the switch is not actuated, should be infinite resistance (open) for all
of them.

If it blows just by sitting there, you don't need me, you need an exorcist.
 

indyken46619

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window motor

Hi
I asked the same question about a 2 weeks ago on how to do the motor swap.

Got tons of good info. check the posting or do a search.

So far I have one motor installed in the front passenger door. Can't remeber if it was the right or left out of the E28 but it is easy to determine which one fits.

As was mentioned 2 holes line up but one had to be drill larger. The third I had to drill a new hole.

When you connect the motor use the black and the green and omit the brown ground wire.

Use the E9 swithces add a ground to the 4th terminal - someone mentioned running a wire to the console but I just took the ground off the lighter and connected it (brown) it works fine. I guessed wrong the first time and had to switch the wires - window was going in the wrong direction.

Also had to cut a section of the door panel out - tin snips worked just fine.

Will be working on the rest of the windows - not sure where I'll get the extra grounds for the switches - probable will branch off the lighter wire.

No one has said anything about the rear switches but I guess these will be the same.

I found instructions on how to fix broken switches - I've fixed one and it is working good - let me know if you need the info.
Ken
3.0 CSi 72 226 0090
 

x_atlas0

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Interesting. The armrest and console switches are presumably wired in parallel. The only way you would short the circuit is if one of the switches (either armrest or console) does not quite open when in the idle position. Could be that it is tired mechanically or has lots of deposits making it conduct (hard to believe). I assume the fuse blows when you operate one of the rear windows, not just by sitting there wired the new way. If that is the case
the bad switch is the one you are not actuating when it blows. (If it blows when you actuate the console rear right window, then the right armrest is bad, if it blows when you actuate the armrest switch, then the console switch is bad).

Pull the suspect switch and measure resistance between all pairs of pins
when the switch is not actuated, should be infinite resistance (open) for all
of them.

If it blows just by sitting there, you don't need me, you need an exorcist.

All the switches were fine. It blew fuses when the fonts and rears were connected, when I tried to use the front or rear switches.

As for the exorcist, it might help, given how my rear lights are maddeningly intermittent.
 

Arde

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Hmmm. The only explanation is that both switches are suspect. I assume you checked them to verify they are open when not activated.

As for the rear lights, the main suspect is the rear bulb sockets. The circuit
is pretty simple. The ground could also be loose.

The beauty is that you can troubleshoot the E9 with just an ohmeter. I saw a
330 BMW 2003 in the shop being worked on for about a week to get the brake light to work. The brake light switch goes to some control unit and when that was replaced the headlights stoped working. The unit mas to be reflashed for the particular model, and that means back to a dealer.
 

kurtd

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Thanks to this thead I've almost completed the retro fit of the e28 window motor to the drivers door regulator. The wiring which I though would be the hard part was actually easy. I used the green and blue leads from the wiring harness and connected those to the 2 leads of the new motor. The ground from the wiring harness is not used. The last step was to grounded the 4th pin on the window switch to the cig lighter and it just worked.

I've taken a bunch of pictures along the way with hope of writing this up but I've run into a snag. The gearbox on the new motor is thicker than the old style and when mounted contacts the inner door frame before the bolts can be fully tightened on the regulator. It will actually operate the window but I really don't want to leave it this way. It seems that several other including indyken46619 cutout the door to clearance the motor.

In this picture the black marker highlights the contact point and the portion of the door panel that needs be removed.

IMG_0259.jpg


This image more clearly shows how far the mounting bolt is from reaching its base when the motor contacts the door

gearboxfit.jpg


Has anyone been able to complete the conversion without cutting the inner door frame?

-Kurtd
 

TILLA

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I was able to install my right side regulator using some nylon bushings on the two top bolts between the door sheet metal and the regulator - if I recall correctly one was thicker than the other. The left one I have been struggling with as it is binding. I bench tested it but when I installed it I ran into trouble and am still working on it.
 
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window motors

I was able to use 2 of the mounting bolts and NOT cut anything on the door frame. This was on my '71 2800cs. Everything has been working just fine. If the bolts are not long enough go to the hardware store and buy some longer ones, I may have had to do this. I don't recall.
Good luck and don't cut!
Pete
 

Arde

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I am glad the electricals are fine.

Being averse to surgery, I would try anything before resorting to cutting out pieces of coupe metal. Can the gearbox be put on a thinning diet?
 

Bill 74 3.0 CS

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Thanks to this thead I've almost completed the retro fit of the e28 window motor to the drivers door regulator. The wiring which I though would be the hard part was actually easy. I used the green and blue leads from the wiring harness and connected those to the 2 leads of the new motor. The ground from the wiring harness is not used. The last step was to grounded the 4th pin on the window switch to the cig lighter and it just worked.

I've taken a bunch of pictures along the way with hope of writing this up but I've run into a snag. The gearbox on the new motor is thicker than the old style and when mounted contacts the inner door frame before the bolts can be fully tightened on the regulator. It will actually operate the window but I really don't want to leave it this way. It seems that several other including indyken46619 cutout the door to clearance the motor.

In this picture the black marker highlights the contact point and the portion of the door panel that needs be removed.

IMG_0259.JPG


This image more clearly shows how far the mounting bolt is from reaching its base when the motor contacts the door

gearboxfit.JPG


Has anyone been able to complete the conversion without cutting the inner door frame?

-Kurtd
Which of the 4 motors from the E28 were used. I hear people say that only the rears work on our E9. Did you just use the motor, or the frames as well from the E28?
 

aearch

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w1.jpg
w2.jpg
w3.jpg
the 74 and on is plug and play
you want the rear.
i can take a pic if needed
you have to mount the motor after the window frame and
crank is in, because it wont fit as a unit
you need to use short bolts
heres my fronts
it seems it was fairly straight forward.
At the top bolt, i bent the frame out a bit at the hole on one side
that must be the early style,
the 74 crank system seems to be much easier
 
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Gary Knox

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You can also use the motors from an early Porsche 928. I've forgotten the change year, but the early cars used 8 tooth gears and the later cars used 12 tooth. You would need a pair of the 8 tooth. They are identical to the e28 rear door motors/gearbox.
 

twistinglane

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From the discussion here it seems that it is known that e24 and E23 motors don't fit. It's that correct?
 
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