Window Runners and Felts Replacement

Sunday 10/11/02

Over time the windows of most 928s will develop a bit of a rattle. There are two causes. The first and easiest to repair is the felt blocks on the inside edge of the windows. Over time the rubber core compresses and the felt compacts. If you have tinting on the window this will result in the tint material becoming scratched and the window rattling annoyingly when its half way down.

The second is less problematic, but means the window doesn't run up and down quite straight and will contribute to the rattling. That is the plastic runners on the window's mounting bracket become worn. Its easy to test for. Just wind the window down half way taking hold of the top try to pull it back forth along its lenght (toward the front and back of the car). If it moves a little in either direction then its likely that the contact points on the runners are in need of replacement.

Both the felt blocks and the runners each of Silver's doors were in need of replacement. Badly. The tinting was already scratched on both windows, so will have to come off one day.

Required Parts:

Felt Removal and Installation Procedure:

1. Pick a door and remove the arm rest and lining. I don't currently have detailed instructions for this process, but there are plenty out there on the net.
2. Remove, or slit the plastic lining of the door panel. I am replacing mine so I have removed them entirely
3. Wind the window all the way down and look in the slot in the top of the door. You will see the felt blocks on the inside edge pressing against the top of the glass
4. Remove the black trim strip from the top of the inside edge of the door panel. It holds on hard, but all you have to do is carefully leaver it up with a big screw driver or similar using the flat edge. Start in the middle and work your way forward and back. You don't actually need to take it all off, you can leave the last couple of inches attached and do the job
5. Each block has two halves and a cap screw in the middle (bolt with a hex key / allen key hole in the middle). Because they are recessed a little you will need a hex driver with a bit of reach, a t-bar, or allen key to undo them
6. Be really careful to get the tool deep into the cap screw. If you don't and its sticks a bit then you can strip the hole and make it very hard to get the bolt out
7. Run the bolt out slowly and put your hand under the block inside the door panel. The bolt has two small washers that will probably fall off. If they get down into the bottom of the door panel (especially the smallest of the two) you will be lucky to get them out. More likely they will stay sitting on the top of the block. A magnet is handy to fish them out with
8. Push the blocks down from the top. Keep a hand under each one so that if it falls it won't scratch the window (small chance, but you never know)
9. The blocks are all the same, so you can pick any one. You will need to push it hard to get it into place
10. Once its there, carefully replace the washers (thick one on the bottom, thin one on top) and carefully run the cap screw back in. Tighten them down nice and hard
11. Run the window up and down a couple of times to make sure that everything is working as it should. Test for rattle when it is half way up. You should find that the new blocks hold the window out hard against the outer seal. I have a feeling that this repair will also reduce water intrusion into the doors. I have had particular problems with this, especially when cleaning
12. If your all done and aren't replacing your window runners, replace the trim, plastic skin on the door panel, door liner and arm rest.

Its a simple job, that requires about an hours work if you are new to it to do both doors. But well worth the effort.

I will cover replacing the runners next. That is a longer more difficult process, but worth doing too.