old car

Window Regulators

November 2006:

The drivers door window decided that it would fall down under gravity so inspection was essential and urgent.

broken spring - click for larger image

The door cover was removed to reveal a very simple mechanism.

As well as the obvious broken window balance spring, the clever little spring in the bulge on the pinion shaft was also broken.

window winder clutch components

The housing is attached to the winder assembly by three bent up tags; these will break off when you remove the housing.

Inside the housing is a driving member, a driven member (with the pinion on the end) and the all-important and extremely clever, precision spring.

replacement window winder spring

If the window is pushed down, the loops on the end of the spring act to force open the spring which then binds on the outer casing and stops movement.

If the winder handle is rotated the loops on the end of the spring act to tighten the spring and the resulting smaller diameter allows the spring to rotate freely inside the casing

These springs are very long-lived, but they do break on occasion! - and then you appreciate just how important they are.   They seem to be unobtainable these days and the one new replacement found proved to be slightly oversize and also the end lugs came at the wrong point.

As they are a real precision item you will have to find an original.   It is helpful to know that the springs in the rear winders (even though a very different mechanism) are the same as the front ones.

the complete winder assembly, click for larger image

The housing re-attached to the winder assembly.

spring housing reassembled - click for larger image

Most reaffix them by judicious spot welding but I used pop rivets, araldite and a reinforcing bar, which can be taken apart later if needed.  Clearance to the large gear behind means that you can only directly pop rivet the upper section of the housing.

after reassembly and greasing, the "new" springs worked well.

winder reassembled - click for larger image

The window was easier to wind up and down and, more importantly, couldn't be forced down.