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E39 (1997 - 2003)
The BMW 5-Series (E39 chassis) was introduced in the United States as a 1997 model year car and lasted until the 2004 when the E60 chassis was released. The United States saw several variations including the 525i, 528i, 530i and 540i. -- View the E39 Wiki

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  #1  
Old 10-24-2012, 09:01 PM
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How do we loosen tension on a BMW E39 front window regulator anyway?

EDIT: MatWiz helped us focus on the spring in order to come up with a nearly effortless technique (see post #25, patent pending) which easily loosens & tightens the tremendous cable tension notch by notch.
This almost effortless tensioning method is not documented anywhere else on the Internet to our knowledge!

What is the trick to loosening the tension on a BMW E39 front door window regulator where the cable has jumped off the wheel?

If it's obvious how ... I don't see it.

Here is my 'bench' test apparatus:


And, here is the problem:


Q: What's the procedure for loosening the cable tension to get it back on the last roller?

NOTE:

1) This was the original bmw 2002 525i E39 front driver side window regulator repair DIY
2) This was an update that added the window regulator a year later
3) This is yet another update that attempts to detension the window regulator
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Last edited by bluebee; 11-04-2012 at 09:48 AM.
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  #2  
Old 10-24-2012, 11:07 PM
radd radd is offline
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this job is super hard... I ended up cutting the rubber spring that work as a cable limiter/holder when goes in to the center loop, but this just to get reassemble the whole thing. I haven't tried to test it so I have no idea whether it works or not

I would like to know how too.. otherwise we all have just stick to "Just buy OEM part, dont fix it or buy aftermarket ones"
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  #3  
Old 10-25-2012, 04:21 AM
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BB: I haven't done this repair so this is pure speculation:

In your first picture, there looks to be a spring on the cable assembly (near the motor?). If you compress the spring, does that introduce slack into the cable system?

In your second picture, it looks like the wheel has a broken section of the flange at the 7-8 o'clock position. Did the cable jump the wheel during operation? If yes, that broken flange may be why. It may need to be replaced or this could happen again.
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  #4  
Old 10-25-2012, 07:23 AM
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I don't know how this applies to the front regulator, but I just had it happen to my rear one. I tried placing the cable back on the wheel, but it just seemed impossible. I opened up the motor where the cable goes in/out and saw that there was some additional slack of the cable caught looped inside, which also prevented the motor from moving either direction. After fixing that and assembling back the motor it still seemed like I need to apply a lot of force to get the cable back on tracks. What I ended up doing is removing one of the cable ends from the slot it sits in next to the motor (where the cable spring is), which created enough slack in the cable to loop it around all pulleys, and then wrestle the cable end back into the slot and it worked. What surprised me is how much tension the system rests/operates under and with all plastic pulleys and steel cable...
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  #5  
Old 10-25-2012, 07:26 AM
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BB, sounds like your motor is moving fine, so in your case you probably don't need to take the motor apart. But if you do, pay attention to how the cable sits inside, it's a bit tricky getting it back on the internal pulley.
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  #6  
Old 10-25-2012, 08:04 AM
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Quote:
Originally Posted by radd View Post
I would like to know how too.. otherwise we all have just stick to "Just buy OEM part, dont fix it or buy aftermarket ones"
I don't see anything wrong with the regulator so I'd rather figure out how to release tension.

Plus, I've googled and I don't (yet) see any other threads showing a stop-by-step way to release the tension ... so ... if we, together, come up with a good idea, the resultant DIY will benefit those who follow.

Quote:
Originally Posted by Fudman View Post
If you compress the spring, does that introduce slack into the cable system?
Let's make mechanical spring compression "Plan A".

I'll check and report back.

Quote:
Originally Posted by Fudman View Post
the wheel has a broken section of the flange
The wheel is chipped, but, I don't think that's why the cable slipped off the pulleys because the tension is astronomical, which should keep the cable on the pulley (I think). Of course, if the wheel truly 'is' the problem, the regulator is toast, and the solution morphs to a simpler solution because I can experiment with releasing tension without being worried about further damage to the regulator.

So, even with a chipped wheel, the problem still remains ... which is to figure out how to cleverly release tension.

Quote:
Originally Posted by Flug540 View Post
What I ended up doing is removing one of the cable ends from the slot it sits in next to the motor (where the cable spring is), which created enough slack
I've seen Matwiz' DIY showing the coiled insides of the motor so, I understand what you're saying (where is the wiz when you need him!).

I assume disassembling the motor is "Plan B".

Quote:
Originally Posted by Flug540 View Post
it's a bit tricky getting it back on the internal pulley.
Looking closer at the motor, I see this 'purposeful' plug.

I wonder ... Do you think 'this' can be used as 'Plan C" to loosen tension somehow?
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Last edited by bluebee; 10-25-2012 at 09:01 AM.
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  #7  
Old 10-25-2012, 09:03 AM
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Quote:
Originally Posted by bluebee View Post

BTW, what do you think this square plug is for?



Looking closer at the motor, I see this 'purposeful' plug.

I wonder ... Do you think 'this' can be used as 'Plan C" to loosen tension somehow?
A square tool interface is highly unusual. It would require a specialized tool or a flat blade screwdriver jammed into it to turn it. This suggests that adjustment of that plug is rare. I would check to see if the plug is tight or loose, using a screwdriver. If it is tight, leave it be. If it is loose, rotate it one way or the other a half turn and watch to see if the cable tightens or loosens up.
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  #8  
Old 10-25-2012, 12:09 PM
dvsgene dvsgene is offline
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Oh no, you did not heed my warning about how hard it is to re-assemble in your original post! But wait, did the cable just come off while in operation?

I wanted to mention in you original post that the chip might be the end of the regulator unless you replace the roller which is why I suggest a call to RegulatorUSA.

Did you call the regulator guy in Brooklyn to see if he sells just the rollers he uses?

I think the cable will still jump off the roller if the chip is not fixed. Reason being, the cable is under great tension as you found out. The cable itself has a tendency to want to recoil naturally so as the cable moves around the roller, the cable twists, as it twists, it will jump off the roller. Remember, the cable is nothing more than twisted steel wire and twisted steel has the tendency to twist in the direction of the winds.
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  #9  
Old 10-25-2012, 08:55 PM
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Quote:
Originally Posted by dvsgene View Post
did the cable just come off while in operation?
The cable came off in testing - but I don't think it was due to the chipped roller; I think it was because I had not tightened everything - and/or because the window was out of adjustment, as there is not a well defined procedure (despite the Bentleys, which are worse than confusing) for adequate adjustment of the stops.

BTW, I pulled out the square plastic bolt - but it doesn't seem to be of any benefit in loosening the tension. All it does is plug the hole, perhaps so that we can add grease to the motor helical gear.


At some point (I don't know when), the smaller springed tube fell out of its slot in the motor housing.


In hindsight, here is how that tube 'should' have been reassembled:


Another mistake I made (of many) was to not realize that this ribbed black plastic spring-tension adjuster might be a critical component in loosening cable tension!

I should at least have marked the initial location of the black plastic large spring stop, so that I would know how much to push it back into the motor when I put it back.
Here is that black plastic ribbed spring stop, almost pulled out:


I spent some time trying to figure out how that larger black plastic stop goes into the motor - and finally concluded it's a press fit - which takes a LOT of force to fit inward - and which is mighty hard to perform with that heavy spring in place (more about how to conquer that all-important heavy spring comes later).


Boing!

While I was examining the motor for how to release tension, curiosity got the better of me.

This gear is what spins the coils of cable.

Notice each coil is wrapped around the takeup spool twice, in opposite directions.
The large spring cable is coming in from the left; the smaller spring cable comes in from the right.

Within seconds of snapping that photo for you, as I put the camera down, that nice arrangement of cable coils literally unwound in my hands.

Leaving me with an unsprung front window regulator takeup spool.


After all this - I belatedly realized (what might be) the trick to reduce tension on the front window regulator!
Look at this picture below.

Notice you can easily unhook the heavy coil spring from the cable, and hook it back up easily after the fact, simply by unwrapping it from the wire as you would unhook a key from a common keychain.

I'm guessing this spring unwrapping can be performed without disassembling anything!

If so, that's the trick to releasing tension (WITHOUT DISASSEMBLING ANYTHING!)

It's too late for me to try this trick - but - if I had known that I could simply unwrap the heavy coil spring, I would have tried that, instead of ending up with motor parts all over the place.
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Last edited by bluebee; 10-26-2012 at 05:38 PM.
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  #10  
Old 10-25-2012, 11:04 PM
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I practiced removing the spring off the cable a few times.
Of course, strong tension is gone - but, I proved to myself the concept of removing the spring without disassembling anything is sound; so, here's my proposal (for the next person) of the trick to loosen cable tension without disassembling anything else:

To loosen cable tension, this may be the best potentially viable approach:
  1. Measure the current location of the black ribbed plastic large-spring stopper
  2. Push the black ribbed plastic large-cable stopper in all the way
    • That, in and of itself, may provide enough tension relief
  3. If not, first, you may have to pull the black ribbed plastic large-spring stopper out an additional inch or so
  4. Then, unwind the large spring off the cable (like pulling a key off a keychain)
  5. When it's time to replace the spring, wind it back on (like putting a key on a keychain)


Had I known that potential trick of unscrewing the large spring, my regulator would never have been taken apart ... but ... I guess someone has to take the hit so that the next person has an easier time of it.

The good news is I now know more about this window regulator than I ever wanted to know - and I certainly have learned a host of things NOT to do!

The bad news is that it would take a minor miracle to get it all back together again.


Things not to do:
  • In hindsight, I wish I had marked the location of both window clamps to the guide rails because they probably need to be symmetric on the rail cable guides when I restring the cable.
  • Also, I wish I had marked the amount of cable wound inside the spool because that is probably a critical dimension (I should have put a dab of nail polish on the two cables at some strategic point)
  • I wish I had marked the original length the black ribbed plastic large spring stop stuck out of the motor (as it can move at least an few inches either way).
I'll ask MatWiz for advice how to proceed ... he (Dan) seems to be the only one who documented the motor disassembly (but he stopped half way when his camera battery died):
-> E39 (1997 - 2003) > Front Window Regulator - Re-Assembly Instructions.


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Last edited by bluebee; 10-26-2012 at 01:35 PM.
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  #11  
Old 10-26-2012, 01:45 PM
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MatWiz MatWiz is offline
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Quote:
Another mistake I made (of many) was to not realize that this ribbed black plastic spring-tension adjuster might be a critical component in loosening cable tension!
You are right. It IS critical to loosening and tensioning!


Quote:
I should at least have marked the initial location of the black plastic large spring stop, so that I would know how much to push it back into the motor when I put it back.
Here is that black plastic ribbed spring stop, almost pulled out:
No need to do this, that thing is self adjusting, self tensioning!

OK, this was 5 years and 2 months ago, so I might not remember everything I did so this is to my best recollections. (Damn camera battery!).

IIRC, the black rigged piece works counter intuitive. The spring pushes it out. When the spring pushes out, the tension increases on the cable.

Also, the black piece works like a ratchet. Once it is pushed out one ridge by the spring, you can not push it back in. Or is it the other way around? I don't remember which way the ratchet works, but I do remember that it is a ratchet.

So the trick was to hold the spring compressed as much as I could, then put everything in its place, and then release it to create the tension. The tension is not adjustable, the spring creates the tension and there is nothing you can do.

I hold the spring compressed so that I have some play with the cable, so that I could put all the parts and the cable in its place, I used a kitchen fork. Stick the fork in the spring and push it against the metal housing. I had to bend one of the middle fingers of the fork to allow it to go around the black piece.

To my best recollection, I put the cable around the rollers, then compressed the spring, and only then pushed the spiral wheel into its housing.
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Last edited by MatWiz; 10-26-2012 at 02:18 PM.
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Old 10-26-2012, 02:30 PM
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^^^ I don't like how the cable is bent over there. Something or someone installed that incorrectly or maybe it got dislocated. But look at my picture, they are completely strait:


So when you wrap the cable ends around the spiral, make sure you insert them flush in their grooves.


Another tip, the plastic housing kept jumping out of the metal housing when I tried to put everything together. I finally figured to tie it down with these strips until it was assembled. Then I removed them after.

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Old 10-26-2012, 02:56 PM
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Q: How to wind the spool / spiral?

A: It doesn't matter (!). As long as you 'load' all the groves with both ends of the cable. Once you loaded them, put the spool halfway inside its housing and turn it with your fingers to see who it works. You'll see that as it releases cable on one side into the rails, it will pull in the same amount of cable from the other side. Once one end reaches the end of the cable, the spool will stop, naturally. Turn it the other way and it will stop on the other side. Meanwhile, the spool is always full of cable, either from one side, or the other, or half and half. End to end is exactly the distance that the window is moving up and down. You can't make it wrong as long as you don't leave on groove completely empty, and it doesn't matter from what side of the cable.

I suggest, that for practice and to see how it assemble without the tension, assemble everything without the spring, but with the black piece.

To my BEST recollection, when I assembled everything, the last piece I put in was the spool. I left the spool out, compressed the spring, and then pushed the spool into its place.
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Old 10-26-2012, 06:24 PM
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Quote:
Originally Posted by MatWiz View Post
It IS critical to loosening and tensioning!
So that's the answer to the question of how to loosen cable tension!
I wish I had known that earlier - when I needed it!

The good news is the NEXT person can start without making the same mistakes!

Quote:
Originally Posted by MatWiz View Post
IIRC, the black rigged piece works counter intuitive. The spring pushes it out. When the spring pushes out, the tension increases on the cable.
Is this correct yet?
  • Push the black plastic ribbed post into the motor ==> decreases cable tension?
  • Pull the black plastic ribbed post out of the motor ==> increases cable tension?


Quote:
Originally Posted by MatWiz View Post
the black piece works like a ratchet. Once it is pushed out one ridge by the spring, you can not push it back in. Or is it the other way around? I don't remember which way the ratchet works, but I do remember that it is a ratchet.
I agree it's confusing. Like you, I found the ratchet post does NOT spiral inward. Each "rib" is a 'stop'. However, I found, with force, the ribbed tension adjuster 'does' go both inward and outward - but it takes a LOT of force either way. I had to actually use a mallet on it, which is difficult because the spring was there (this was before I knew HOW to unwind the spring in situ!).

Quote:
Originally Posted by MatWiz View Post
So the trick was to hold the spring compressed as much as I could, then put everything in its place, and then release it to create the tension.
Another trick 'might' be to assemble the cables without the spring (taking care to put the black ribbed plastic post in a 'desired' setting), and then manually wind the spring onto the cable like how you put your key into a keychain, spinning it on the cable, one turn at a time.

Quote:
Originally Posted by MatWiz View Post
The tension is not adjustable, the spring creates the tension and there is nothing you can do.
Oh oh. What does that mean? I wasn't confused when I thought that the LOCATION of the black ribbed post is what determines the tension on the cable.

If the spring in and of itself creates the same tension no matter where the black ratchet post is set to, then what does the ratchet mechanism do?

Quote:
Originally Posted by MatWiz View Post
I hold the spring compressed ...I used a kitchen fork.
Do you can see a small hole in the white plastic that the spring goes around in one of my pictures? I tried holding the spring in place with a nail pushed into that hole. However, the spring is POWERFUL. It pushed the nail out - but - with diligence - that hole might be used to hold the spring in compression.


However, I hope that the spring can simply be wound onto the cable as the LAST STEP!

Quote:
Originally Posted by MatWiz View Post
I don't like how the cable is bent
I had noticed that same difference the moment I saw your pictures. Your cable ends in the take-up spool are both straight. Mine are both bent. My cable is also slightly frayed as a result.

I carefully straightened them by hand.


Quote:
Originally Posted by MatWiz View Post
when you wrap the cable ends around the spiral, make sure you insert them flush in their grooves.
I fully understand.

Quote:
Originally Posted by MatWiz View Post
I finally figured to tie it down with these strips until it was assembled.
I had noticed that. I was thinking I might do one of three things to prevent that problem:
  1. Tie it down just like you did
  2. Bolt it down using the original bolts and the original motor mount plate
  3. Skip the step altogether by (hopefully) winding the tension spring on as the VERY LAST STEP! (if that works)
Quote:
Originally Posted by MatWiz View Post
Once one end reaches the end of the cable, the spool will stop, naturally. Turn it the other way and it will stop on the other side. Meanwhile, the spool is always full of cable, either from one side, or the other, or half and half.
Hmmmm.... Interesting!

Quote:
Originally Posted by MatWiz View Post
End to end is exactly the distance that the window is moving up and down. You can't make it wrong
Hmmm... I guess this is one thing I have to try first to best understand!

Quote:
Originally Posted by MatWiz View Post
assemble everything without the spring, but with the black piece.
Well, if my gut feeling is correct, I might be able to assemble the entire thing, and even bolt the motor back to the motor plate, without ANY tension. Then, as a very last step, I will try to wind the spring back onto the cable, from the outside inward (if that will work) just like you put a key on a keychain.

If 'that' works - the tension would be the last step!

Quote:
Originally Posted by MatWiz View Post
the last piece I put in was the spool. I left the spool out, compressed the spring, and then pushed the spool into its place.
Interesting. I was planning on doing the takeup spool FIRST!

This is good advice that the takeup spool can be handled later!

Thank you for taking time to help. I realize it was years ago (your thread was from 2007!), and I'm soooo very glad you posted such great pictures. I scoured the Internet, and, to my knowledge, you're the ONLY one to have done so for the E39!
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Last edited by bluebee; 10-26-2012 at 06:40 PM.
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  #15  
Old 10-26-2012, 07:16 PM
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Bluebee, can you first take a closeup picture of the black piece ribs, to clearly show the ribs, and post here?

(I want to see the "ratchet").
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Last edited by MatWiz; 10-26-2012 at 07:27 PM.
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  #16  
Old 10-26-2012, 08:25 PM
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Quote:
Originally Posted by MatWiz View Post
closeup picture of the black piece ribs, to clearly show the ribs
Hi Dan,

Here are closeups of the ribbed post. (I'd be glad to snap any photo at any angle you need. Just ask. You're helping me. And the next person. And the next after that.)

It seems to me, as it appears to you, that this mechanism is the missing link.

What puzzles me is why have an 'adjustable' post - when - I've never seen any mention of anyone actually adjusting it?

The post really only 'locks' into place into the motor tube. While it 'can' be pushed down a few notches or pulled up a few notches, it's meant to stay in place once configured.

Since it can be locked in any position ... an understanding of what's different when it's all the way in versus all the way out is key to understanding these window regulators.

My gut feeling is that the post "is" the tensioning mechanism, somehow ... but I'm not exactly sure how. Either that, or it's just for assembly purposes.

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Last edited by bluebee; 10-26-2012 at 08:29 PM.
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  #17  
Old 10-26-2012, 09:00 PM
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Quote:
Is this correct yet?
Push the black plastic ribbed post into the motor ==> decreases cable tension?
Pull the black plastic ribbed post out of the motor ==> increases cable tension?
Yes. This is correct.


Quote:
My gut feeling is that the post "is" the tensioning mechanism, somehow ... but I'm not exactly sure how. Either that, or it's just for assembly purposes.
Not maybe. I am telling you that this is the tensioning mechanism.

I just don't remember exactly how exactly it behaves when assembling because it has been such a long time.

But, I just wanted to verify something and it seems that I was correct in my memory. Look at the ribs, that's a ratchet. If I can see correctly in your picture, the ribs are angled in such a way, so that the piece will be able to more easily outside, and will be harder to move back in. The ribs shape like an arrow. Can you see that?

That's why I said that once it moves out one rib, it can not move back. The spring and the angle of the rib prevent it from moving in. And that is the self adjusting mechanism. It keeps the cable tight on the rollers. You can't lock it in place. It is designed that the spring gives it the desired tension, and if and when the cable loosen up in time, the spring moves the black piece out a rib, and keeps the tension.
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Old 10-26-2012, 09:07 PM
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Do a 'dry try' to assemble the whole thing but without the spring. That will make it much much easier. Then, pull the black out and hold it there with your thumb and your fist (to imitate the spring) and turn the spool with a long nose pliers, and you will see exactly how the whole thing works and a lot of questions will be answered. If not for nothing else it will help you assemble it with the spring later on. Practice makes it easier... one should hope.
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Old 10-26-2012, 09:37 PM
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Originally Posted by MatWiz View Post
I am telling you that this is the tensioning mechanism.
Thanks. Too bad I didn't know this before I took it apart - but - let's try to document its function moving forward so that the NEXT person benefits.

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Originally Posted by MatWiz View Post
it has been such a long time.
I understand. Your DIY thread was posted in 2007!

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Originally Posted by MatWiz View Post
the ribs are angled ... like an arrow. Can you see that?
Yes. And, empirically, I think it was much harder to pound the adjuster post inward (into the motor) than it was to simply pull it out (out of the motor).

The strange thing is you'd expect the exact opposite!

That is, the spring tension is clearly placing a force on the head of the ribbed adjuster post such that there is tension pulling it OUT of the motor - yet - it seems to stay in place (probably due to the design of the white plastic 'catch' inside the white motor tube?).

So, for whatever reason ... the post is not supposed to go into the motor as easily as it's supposed to be pulled out.

Given that pushing it in apparently decreases cable tension, that would mean that it's designed to allow an INCREASE in cable tension - but not a decrease.

Maybe it's a cable-stretch compensator?

Quote:
Originally Posted by MatWiz View Post
That's why I said that once it moves out one rib, it can not move back. The spring and the angle of the rib prevent it from moving in. And that is the self adjusting mechanism. It keeps the cable tight on the rollers.
Ah! So it 'is' a cable-stretch compensator. It's a self-adjusting tensioner of sorts!

Quote:
Originally Posted by MatWiz View Post
You can't lock it in place. It is designed that the spring gives it the desired tension, and if and when the cable loosen up in time, the spring moves the black piece out a rib, and keeps the tension.
I see. It is adjusted in one place, and then, as cable tension slackens, it's pulled out a notch, to take up the slack in the cable.

If that's the case, then pushing it in a few notches should LOOSEN the cable. Right?

Quote:
Originally Posted by MatWiz View Post
Practice makes it easier...
I think I'm getting way too much practice on this BMW window regulator!

Thanks for your help. You put a lot of the puzzle together (are you an engineer?).

Here is a photo of the regulator when I pulled it out of the door.
Notice that the cable tensioner was almost all the way in at that time.
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Last edited by bluebee; 10-26-2012 at 09:38 PM.
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Old 10-26-2012, 10:52 PM
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Yes. And, empirically, I think it was much harder to pound the adjuster post inward (into the motor) than it was to simply pull it out (out of the motor).

I'm surprised by the pounding (you said malet previously). Without the spring or without tension (when the cable is loose), you should be able to push and pull the black piece by hand.

Quote:
The strange thing is you'd expect the exact opposite!
That's why I called it "counter intuitive)!


Quote:
That is, the spring tension is clearly placing a force on the head of the ribbed adjuster post such that there is tension pulling it OUT of the motor - yet - it seems to stay in place (probably due to the design of the white plastic 'catch' inside the white motor tube?).
It stays in place because the cable is pulled and tensioned to its limits. I think the 'catch' is there to prevent it from going IN, and loosen the tension. Think of it like the alternator or water pump belt. They want it to always be tensioned.


Quote:
So, for whatever reason ... the post is not supposed to go into the motor as easily as it's supposed to be pulled out.
Right. Imagine you go on a big pothole and the shock causes the spring to compress? You don't want the cable to jump out of a roller. You want this to always be at maximum tension.

Quote:
Given that pushing it in apparently decreases cable tension, that would mean that it's designed to allow an INCREASE in cable tension - but not a decrease.
Exactly.


Quote:
Maybe it's a cable-stretch compensator?

Ah! So it 'is' a cable-stretch compensator. It's a self-adjusting tensioner of sorts!



Quote:
I see. It is adjusted in one place, and then, as cable tension slackens, it's pulled out a notch, to take up the slack in the cable.
Depends what you mean by "adjusted". By whom? If you mean by the spring - then yes. "We", can not adjust it in one place because the spring will always push it out, to the maximum tension, as determined by the spring expansion force.


Quote:
If that's the case, then pushing it in a few notches should LOOSEN the cable. Right?
Yes, but the spring is going to push it right back. There's nothing you can do to loosen it. You push it in to loosen the cable just so that you can reassemble it. Then when you let go of the spring, out it goes to full tension.


I think I'm getting way too much practice on this BMW window regulator!

Thanks for your help. You put a lot of the puzzle together (are you an engineer?).

>>> Electronics, and then I worked on big military radars, so there's a lot of mechanical aspects to that too. But that was a long time ago.

Quote:
Here is a photo of the regulator when I pulled it out of the door.
Notice that the cable tensioner was almost all the way in at that time.
Nice glasses....
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Old 10-26-2012, 11:07 PM
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Originally Posted by MatWiz View Post
Without the spring or without tension (when the cable is loose), you should be able to push and pull the black piece by hand.
I was pounding with the mallet but at that time, the spring was still engaged - so I was fighting the spring.

I agree, it goes much more easily without the spring!

Quote:
Originally Posted by MatWiz View Post
"We", can not adjust it in one place because the spring will always push it out, to the maximum tension
This is good information to get my bearings on how the thing works.

Quote:
Originally Posted by MatWiz View Post
You push it in to loosen the cable just so that you can reassemble it. Then when you let go of the spring, out it goes to full tension.
In hindsight, that's what I should have done to loosen the cable tension in the first place!

BTW, in my googles, it seems the Germans use this particular type of window regulator:
- VW
- Boxter
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Last edited by bluebee; 10-27-2012 at 06:35 AM.
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Old 10-27-2012, 07:30 AM
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If you put it back together and take pictures, you can complete my DIY.
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Old 10-27-2012, 09:22 AM
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If you put it back together and take pictures, you can complete my DIY.
I like the idea of working together to complete your DIY so that others benefit in the future, long after we're gone.

The great news is that we have the holy grail in hand, which is the trick to loosen & tighten the extreme cable tension, at will:
  • The ribbed stem 'is' the tension adjustment mechanism (outward=tighter)
  • The spring can potentially be wound off or on without disassembly of anything
In fact, I just now created a special tool for re-inserting the ribbed stem because it is so difficult to pound that tension adjuster inward (i.e., in order to lessen tension).

So, I'll snap pictures - but - for some reason - for the first time ever, I am no longer privileged to upload photos. I don't doubt that I post more photos than almost anyone - but - I didn't get any private messages from any moderators or system administrators (and I have email turned off) - so I'm not sure why all of a sudden, after all these years, my picture-posting privileges are missing.
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Last edited by bluebee; 11-04-2012 at 10:28 AM.
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Old 10-27-2012, 11:13 AM
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No worries. We all can not upload attachment at the moment. They are upgrading our servers during the whole weekend. You missed the "Announcement" at the top of the forum.

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Bimmerfest Servers Being Upgraded this Weekend (Potential Downtime)

We will be upgrading the servers that run Bimmerfest.com over this weekend to provide a better browsing experience. The biggest interruption will be attachments being shut off during the transition phase but should be back on within 24-48 hours of the move. There will also be a few software updates that may cause you to get a message that the site is not available right now. These will be happening during off peak hours and should be held to a minimum.

The IP address of the site is changing and may be cached by your browser or computer. If you have any trouble accessing the site, try closing your browser and restarting it. If that does not work, you can try restarting your computer.

We look forward to having this upgrades in place and providing a more speedy browsing experience.

Thank you for bearing with us!

-- The Bimmerfest Team
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Last edited by MatWiz; 10-27-2012 at 11:17 AM.
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Old 10-27-2012, 11:32 AM
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You missed the "Announcement"
Oh. Whew! I thought I was suddenly a persona non grata because I uploaded so many pictures of this endeavor.

Success at last!

In the end, it was actually trivial to re-tension my front window regulator.
I'll send the pictures of each step to MatWiz to complete his DIY ... but here is the secret.

The key to releasing tension is shown in this picture!

Without MatWiz' wizardry, I wouldn't have known to concentrate on that spring on that black post!

After focusing on the springed black ribbed tensioning rod, I was E-A-S-I-L-Y able to get the cable onto the rollers.
The extreme cable tension was no problem at all because I simply added the extreme tension as the very last step, one spring roll at a time!

I wish I had not needed to ask so many questions and to learn so much in hindsight (instead of foresight), but, here, for the next person, is the 'idealized' way to release tension:

To release tension:
  • Simply spin the large tensioning spring off (as you would a key in a keyring)
  • Each revolution of the spring will decrease the tension, until there is absolutely no tension whatsoever!
  • Once the spring is off (or nearly off) you can easily pull the (now loose) cables off the pulleys
To add tension:
  • First push the (now naked) ribbed tension rod inward (about 1/2 inch sticking out)
  • Then, string your (loose) cables around the four pulleys
  • Lastly, simply spin the large tensioning spring onto the ribbed tensioning rod (each turn adds tension!)
Voila!


I do have one question of the Wiz, though:

I'm not sure WHERE to measure from, but, the position of the two hexagonal "barrels" seems to be 'off' by about a quarter of an inch.

Q: Where do I measure from, and, should they be closer than 1/8" symmetric?

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Last edited by bluebee; 10-31-2012 at 04:21 PM.
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