Window Seal Replacement

Window Seal Replacement

OK Gentlemen, I admit I'm not sure how to proceed with replacing the outer window seals in my doors....
I bought new ones (expensive!) since the old ones are starting to show cracks and looking old. Went into the doors since I had to troubleshoot and repair the power door locks anyway.

Studied the service manual, and now this is looking like the job from heck... :-(
Do you really have to remove the outer window trim pieces to change these seals? I've never been able to get those darn thin trim pieces off without bending them. Not to mention scratching the paint, ruining clips, etc. Add feeling like a moron because I don't know whatever the tricks are the pros use....
(The service manual says only to remove them, no hint of how.)

82 auto (Moss Green Metallic)
928OC charter member
Florida plate: "V8 SHARK"

You can put the window seals in without removing the trim. You need some seal compatible lubricant. I use sil-glide (silicone gel in a tube). You start at one end and work the small ridge in the gasket into the small outer groove in the trim. The rest just falls in after you've gotten the groove part started. It is fiddly work and if you try to hurry you will wreck the seal. I have a dull, polished butter knife that I use to aid such procedures. If you use a metal balde to help install the seal you need to make sure you hold it at an angle that doesn't scrape any metal parts. If you do you will need to mask and spray with SEM satin black trim paint to restore.

This is all alot easier than it sounds.

Try and look that up in your owner's manual! heh heh

Jay K.

Having worked in an aerospace paint shop, I shuddered when I read this. Silicone kills paint adhesion wherever it touches. I would suggest using a non-silicone lube.


I have used this stuff for a long time. If you apply it to the seal beforeinstallation it helps to keep the rubber slippery. I use it instead of petroleum products (the other large group of lubricants that are readily available) because it won't degrade the seal or blister paint over time. I do agree with you that silicone is a bad thing around areas that are being prepped for paint but I don't think they are bad around properly painted components. I use it because it is compatible with most rubber sealcomponents. More compatible than petroleum based.

Probably the best stuff to use is surgical (water based) jelly but I don't keep that stuff around my shop.

I too have been around commercially applied finishes my entire adult life. That includes powder coating as well as wet electrolytic finishes and currently Teflon finishes. I have been designing products and been responsible for specifying finishes and adhesives in more than a few industries including aerospace. What I have found is that silicone adhesives, when they cure, are almost impossible to get off of a surface that is being prepped for paint. Old style RTV (Room Temperature Vulcanization) windshield caulk is a prime example of this. Silicone adhesives (caulks) have powerful surfactants (vinegar smell) in them that etch into surfaces to enhance bonding. Silicone lubricants do not!

I have applied wax and trim paint after using silicone jelly. I wipe up the area with cheap rubbing alcohol from the Grand Union down the street and a lint free cloth. I normally steel wool or lightly sand the area that will be touched up with paint. I then can apply trim paint (SEM primerless satin black) and it doesn't come up over time. You can tell immediately if the surface is contaminated because the paint won't sheet (flow) over the bad spot.

Jay Kempf

79 US 5 speed

Well, I had all the right part nos for the rh door seals, guides etc, but when I looked at the seal rubber -in P speak 'outer slot seal', it was actually a left hand slot seal, with the up curve at the rear. OK we will do the left door. Wasn't sure if inner liner had to come off, but I got it off. The book just says to pull off the rear unlock know, but mine had a small recessed cap that had to pried off, to reveal a screw holding the knob on the shaft. Quite a bit of the plastic was breaking, so it took a few selected washers to retain again afterwards.

With the glass down, I could see the bumpers, or felt faced block keeping the glass out towards the outer seal- mine seem to be in good shape. Turns out you can do the outer seal without pulling the inner skin. If you look at the outer bottom edge of the new seal you will see a small bead of ~2 mm or less facing down, with a small edge tapering to a point facing sideways. This bead goes in a fine slot on the metal finisher. My old seal was very hard and cracked, so with the glass right down I just started pushing it inwards at the rear until it broke away from the outer black metal finisher. The small bead broke off and came out as a separate piece all the way. Once it starts it is easy to work along. Clean the groove of dust and old rubber.

I lubricated the groove and bead with some Armour-all to ease the insertion a bit. Glass down all the way, feed the curved up end into the rear, and the felt faced curved parts inside the door, but outside the glass, and start the bead into the fine groove. At first it seems impossible, but it will go . Sometime I pushed in with a fine 1/8" wide driver blade, and once started, use the handle end (~ 3/4 to 7/8" dia) to roll along the top edge to force the bead in -see Dan's window page for a pic of using a screwdriver handle to push in the door frame seal - same basic method. It took me a while to get started, but after a while it came quicker, and in the end it all looked pretty good. It seems to go better rolling the whole rubber thing outwards, but this leaves you with the inner felt faced bits above the glass, so then you have to ease these bits behind the glass, ie between the glass and the door skin - thin blunt blade like a butter knife will do it safely. Thanks Dan for your pics and notes.

Had a rest, though, well I have the skin off, lets look at the guides. Yes, the bottom one is loose, giving the rattling noise of the window when you shut the door with glass half down. Read all the notes again, quick drink (110F out there), pull the vertical post out - easy. I even have the new bottom rubber thing, but the old one isn't bad. Hmmm these new guides donít look right. MMMMMMMM, Damn! they are handed, and these are for the right side. Oh well, I learned a lot, lets put it back together. da di da di da ... what was that that fell inside the door as I try to refit the bolts into the top guide - !@#$%^&*( - the blind nut from the OUTSIDE of the glass!!!.

Short pause to gather my composure.
This fell out because it is a shallow (3/16") piece of ~7/8" hex, drilled and threaded, mounted in a piece of plastic to cushion it from the glass. the plastic has two ears to locate in slots in the metal and glass - one had broken off with age and heat, and trying in to get the top guide piece located I had pushed on one of the ears, it broke off and the nut fell out. If it had been the front one, it would have been a glass out job. The guide piece has cavities in it to clear these ears, but..... be warned.

Yes, we can get it back in place with one hand, wont have to pull the glass. Now I cant get the hole to line up. I need more hands here - glass is tipping forward.... loosen top of post mounting bolts. Eventually I got it back in. One thing to watch - the slots in the lower guide piece are lined with Al, to handle the loads of the bolts through them, but they distort in use, and to re-use them you need to clean up any damage in there so the bolts will slide easily to adjust the glass in<->out so it meets the slot in the top properly - BTDT. All back together, check for easy up/down, ok, check meets top slot seal, adjust bottom of glass in to move top out, ok, lock it all up. I run the glass right up, locked up the top of the post bolts, then glass half down to lock up the guide bolts. Just resting now before putting the inner skin back on. The right door should go a lot better I hope. Then I need to get guides for the left door and come back to it later.

John Pitman
83 Euro S A/T White/white 41K Mile

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