door windows scrape and whine when opened

[77 Pontiac]

Hi all,

My 77 Formula has power windows, when I roll the window down it makes a horrible whining noise and I have also noticed a long scratch-line on the glass near the front of the window.

I am guessing that there is some steel to glass contact inside my door, but before I rip i apart is there some feltpads or anything that is the likely cause?

[b_hill_86]

Likely the guides with worn or missing felt

https://images.app.goo.gl/j66Dt7qniVNUYueo6

I’ve seen replacement felt kits but from what I’ve read a lot, if not all, are basically the loop side of hook and loop (Velcro) strips with the Velcro being much cheaper to source and cut to fit.

[Wallington]

Ya, 3 guide blocks behind door trip top. Later years usually had felt on 2 of the 3, early used all. You can basically match the scrapes to where it's touching, and no, you can't polish glass to remove a scratch like that. There's also fuzzy guides on the front track just below where the mirrors mount, that tension the glass when fully up.

Depending on costs, you can replace the felt with your own stock or get a complete set of new blocks which have been available a few years now. These are basically the same as original so already know they won't last long term!

I had a write-up years ago with what I did but must have been pre-crash. Here's a few of the pics just for ideas. Back then there were none reproduced, and now that they are they aren't cheap either.

I had my original guide blocks replated, I bought some thicker felt from Germany and wrapped it right around on itself with contact glue. I'd tried even thicker in the past but had limited adjustment room. Shows the thickness compared to the repro felt that was available at the time for repairs, likely same as what is used in the new sets.

Window guide repro vs 3mm felt 2 by Ben, on Flickr

Restored replated door glass guides felts 2 by Ben, on Flickr

Restored replated door glass guides felts 1 18x3mm by Ben, on Flickr

This is the extra-thick woollen felt wadding I tried first on the guide blocks above, it later came in handy for replacing the completely worn off fuzz of the window track tensioning guides. I did a post on these as well, gone also. These are originally riveted on, the glass just touches the point. So I did the same but used tiny bolts and locknuts that are clear of the glass. Until recently these tracks weren't available new again either, but again, they likely just have the fuzz that wears off easily.  I also made the pads twice as wide for extra support, less vibrations. These are nearly all that support the glass when the window is up, other than bolted along the rail and limited pressure the door guides and seals provide when door is open.

Firebird replated window tracks with felt guides (2) by Ben, on Flickr

[77 Pontiac]

Likely the guides with worn or missing felt

https://images.app.goo.gl/j66Dt7qniVNUYueo6

I’ve seen replacement felt kits but from what I’ve read a lot, if not all, are basically the loop side of hook and loop (Velcro) strips with the Velcro being much cheaper to source and cut to fit.

Thank you, so that begs the question is self adhesive velcro strong enough or do people prefer to use contact spray adhesive instead?

[77 Pontiac]

Ya, 3 guide blocks behind door trip top. Later years usually had felt on 2 of the 3, early used all. You can basically match the scrapes to where it's touching, and no, you can't polish glass to remove a scratch like that. There's also fuzzy guides on the front track just below where the mirrors mount, that tension the glass when fully up.

Depending on costs, you can replace the felt with your own stock or get a complete set of new blocks which have been available a few years now. These are basically the same as original so already know they won't last long term!

I had a write-up years ago with what I did but must have been pre-crash. Here's a few of the pics just for ideas. Back then there were none reproduced, and now that they are they aren't cheap either.

I had my original guide blocks replated, I bought some thicker felt from Germany and wrapped it right around on itself with contact glue. I'd tried even thicker in the past but had limited adjustment room. Shows the thickness compared to the repro felt that was available at the time for repairs, likely same as what is used in the new sets.

Window guide repro vs 3mm felt 2 by Ben, on Flickr

Restored replated door glass guides felts 2 by Ben, on Flickr

Restored replated door glass guides felts 1 18x3mm by Ben, on Flickr

This is the extra-thick woollen felt wadding I tried first on the guide blocks above, it later came in handy for replacing the completely worn off fuzz of the window track tensioning guides. I did a post on these as well, gone also. These are originally riveted on, the glass just touches the point. So I did the same but used tiny bolts and locknuts that are clear of the glass. Until recently these tracks weren't available new again either, but again, they likely just have the fuzz that wears off easily.  I also made the pads twice as wide for extra support, less vibrations. These are nearly all that support the glass when the window is up, other than bolted along the rail and limited pressure the door guides and seals provide when door is open.

Firebird replated window tracks with felt guides (2) by Ben, on Flickr

Thank you for that detailed answer, I am located close to Germany, so if you can remember where you got it from I will use the same supplier for sure - It seems like the repo ones are way overpriced and since I have to pay import taxes and overseas shipping I will just re-trim the ones on the car

[Wallington]

Haha you use what you have access to and think will do the job. Back then you could buy rolls of the fuzzy strip similar to stock, I wasn't impressed and knew it already wore out and scratched glass so wanted something better.

Stock used this long fuzzy bristle type, but once it worn patches and the hard base adhesive would scratch. This is a NOS GM piece, not the repro. Pics will show if they use something similar. The repro strip years ago was similar, but shorter.

GM NOS window felt guide block 9615760 (2) by Ben, on Flickr

As it turns out the felt was just from ebay, I just remember it came from Germany, not planned that way. I also added a link in the post at the time, a few guys were keen, long gone now. Back then ebay wasn't flooded with often cheaply priced and cheap quality items from China. That's all I was trying to avoid when buying the felt, good quality vs from China.

Although this is an Australian-link, this could be very similar. Seems to be a German felt specialist, which is what it was. I also just remembered that I used contact glue on the white felt on the first attempt that failed, this one has adhesive-backing and very strong. I've also used it for guides on auto shifter assembly. But anyway, whatever works for you, these are just ideas.

You'll have to measure the opening in the block, I used the widest I could fit there which was 30mm.

https://www.ebay.com.au/itm/234828141742?mkcid=16&mkevt=1&mkrid=705-154756-20017-0&ssspo=pn9zeXdeRku&sssrc=2047675&ssuid=&widget_ver=artemis&media=COPY

[sreta]

https://www.ebay.com/itm/231743970772?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=pn9zeXdeRku&sssrc=4429486&ssuid=2oNLKkLgRHa&var=&widget_ver=artemis&media=COPY

[Wallington]

I checked mine today while there, 30 x 3mm felt on the guide blocks.

20240814_170059 by Ben, on Flickr

And original GM used fuzzy guide near the mirror mount. These will all be swapped out one day for my new glass and restored mechanism and track set with new felts shown in previous pics.

20240814_170127 by Ben, on Flickr