Dann
Active Member
- Posts
- 545
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- Middle Earth
I am amazed at the amount of cash spent on replacing window lift assemblies.
Why do they fail?
a. A small proportion have motor failures.
b. The vast majority fail due to the bowden cables snapping.
Why do the bowden cables snap?
The cables become corroded due to the unavoidable rainwater seepage into the door voids past the sealing strips at the base of the window glass.
Over time the side channels/runners which guide the glass as it is raised or lowered become contaminated and hardened this causes excessive friction and therefore the window lift motor has to work harder, the driver notices that the window seems to take longer to close/open. Apart from the additional strain on the window lift motor the bowden cable also comes under increased strain. Eventually something has got to give and this is usually the corroded bowden cable.
What's the answer?
Maintenance.
Remove door trim panel
Carefully 'Stanley knife' an access slot in the plastic membrane
Operate the window raise/lower function and observe how the mechanism operates (obviously you should not put your fingers inside the door void during this procedure) You should see the nylon blocks sliding up and down in the mild steel guide channels. You should also observe the bowden cables racing over their pulleys. If on close inspection you find serious corrosion in any part of the bowden cable then any further attempts at maintenance would be pointless until the cable is replaced. Mix some clean engine oil with grease in a suitable container and using a small paintbrush lubricate the mild steel channels as far as you can reach.
Now lubricate the bowden cable by raising/lowering the window in small increments and applying the lubricant as each successive section of cable is revealed.
Window runner maintenance
With the window glass fully lowered, impregnate a small piece of sponge with a good quality plastic bumper colour restoration spray and apply this to the extreme edges of the glass also spray this product sparingly into the window side runner felt channels.
Finally gaffer tape the cut slots in the plastic membrane and replace the door panel.
Why do they fail?
a. A small proportion have motor failures.
b. The vast majority fail due to the bowden cables snapping.
Why do the bowden cables snap?
The cables become corroded due to the unavoidable rainwater seepage into the door voids past the sealing strips at the base of the window glass.
Over time the side channels/runners which guide the glass as it is raised or lowered become contaminated and hardened this causes excessive friction and therefore the window lift motor has to work harder, the driver notices that the window seems to take longer to close/open. Apart from the additional strain on the window lift motor the bowden cable also comes under increased strain. Eventually something has got to give and this is usually the corroded bowden cable.
What's the answer?
Maintenance.
Remove door trim panel
Carefully 'Stanley knife' an access slot in the plastic membrane
Operate the window raise/lower function and observe how the mechanism operates (obviously you should not put your fingers inside the door void during this procedure) You should see the nylon blocks sliding up and down in the mild steel guide channels. You should also observe the bowden cables racing over their pulleys. If on close inspection you find serious corrosion in any part of the bowden cable then any further attempts at maintenance would be pointless until the cable is replaced. Mix some clean engine oil with grease in a suitable container and using a small paintbrush lubricate the mild steel channels as far as you can reach.
Now lubricate the bowden cable by raising/lowering the window in small increments and applying the lubricant as each successive section of cable is revealed.
Window runner maintenance
With the window glass fully lowered, impregnate a small piece of sponge with a good quality plastic bumper colour restoration spray and apply this to the extreme edges of the glass also spray this product sparingly into the window side runner felt channels.
Finally gaffer tape the cut slots in the plastic membrane and replace the door panel.
