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Old 10-27-2012, 11:32 AM
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bluebee bluebee is offline
Seek to understand,^Value
Location: San Jose, California
Join Date: Mar 2008
Posts: 25,236
Mein Auto: 02 BMW 525i M54 auto 130K
Originally Posted by MatWiz View Post
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!)

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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Please read the suggested threads and add value, either by pictures or by descriptions, so the next person stands on your shoulders.
See also: E39 Bestlinks & How to easily find what you need

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