FIX for window gap - 740 Series - powered windows
 

I have been petstered by a gap between the corner of my drivers window and its channel when the window was powered into its uppermost position , thereby increasing road noise.

I removed the interior door cover on a number of occasions finally replacing the "tuning fork" shaped pieces of nylon guide, which guide the scissor mechanism.

All of this caused no improvement.

Having duck taped the glass in the up position, I removed the scissor mechanism. There was obvious signs of a problem with a bearing on the scissor which is closest to the gear quadrant. This is formed from a diecast part whose castellations fit and are swaged into a castellated hole in the scissor. The other side of this part has a slot in it for holding one end of a coiled spring.

Mine had been hanging in there for years, and presumably had been rocking and moving there by allowing the pressure on the front edge of the glass to be less than it should be, thereby creating the small gap at the rear corner of the glass.

Using the small lathe that I have, I turned a new part.

The part is identical to the original on the spring side, but to avoid the castellation I made the castellated hole in the scissor circular and made the part fit this hole, but made the shaft of the part slightly longer to allow me to weld it to the scissor.

This being done, the scissor was refitted and the fit of glass to channel is as new.

So if you have the same problem remove the scissor and inspect it. You may be able to get away with suitable re swaging of the part to scissor by means of a punch. If you are taking it all apart note the position of the spring and just in case the part falls out, note the position of the slot in the part relative to the scissor.
Mine fell out as the scissor was removed, which gives you an indication of how bad it was.

No more wind noise !

Regards


Dave Wilson