Duster windshield removal/replacement

-
Ken71Twister

Ken71Twister

FABO Gold Member
FABO Gold Member
Joined
Mar 26, 2011
Messages
313
Reaction score
98
Location
Valparaiso, FL
I have a leak in my 1971 Duster - I’ve had it for many years and it is coming from the windshield on the left and right edges. I had a new windshield installed over 10 years ago by a local glass shop and it leaked after a year or two. I’m assuming they didn’t use the correct “stuff” around the windshield. I talked to a local restoration shop about pulling the windshield and re-installing with the proper sealants. They said the risk of breaking the windshield was too much for they to attempt the job. Is this a reasonable assumption? I just checked and it looks like I can replace a broken windshield for less than $500 - so maybe I’m willing to take that chance. Questions are as follows:
1) What is the correct sealant for the installer to use if the windshield is removed and re-installed or replaced?
2) What’s the chance that a good shop could apply sealant to the existing windshield and stop the existing leaks?
 
Honestly, you should not need any sealants on a gasketed windshield. The rubber gasket itself is the seal.
Sealants are for flush mount windshields.
Most often a shop will use sealants when there are issues with the flange (rust, pits, distortions, sometimes vinyl tops, etc.), are attempting to reuse the old gasket, or they are dealing with an offshore replacement windshield- which often are thinner than originals and don't fit the gasket very well. Or the installer is a rookie.
I'm thinking you may have issues elsewhere- leaking wiper pivot seals, rust in your plenum box (cowl) or windshield channel/flange area, or maybe just plugged cowl drains. I'd hate for you to pay to pull and reinstall the windshield only to still have the original problem.
And if you do decide to have it resealed anyway, and the installer shows up with silicone or anything other than black butyl, send him home.
Silicone is for fishtanks and bathtubs.
 
Last edited:
The glass windshield can't leak, only the rubber seal or bad sheet metal. As Dr Fate mentioned, you should more thoroughly investigate where the water is coming from, then proceed.
 
The rubber is the seal, if using any goo then something is wrong. As above potentially pitted metal or reused seal. Worse case there is a rust hole somewhere
 
I fought this for many years on many a-body mopars until I figured it out. We have a Barracuda here right now with the same problem we have to correct. It leaks at the same place on both sides , Fuse box and top of glove box.

Some cars leak right from new and some don't. Reason why most all of these cars have rusted out floors. Its not the wiper pivots and its not the windshield gasket. When ever you pull the windshield on these cars there is a channel that gets exposed that needs to be resealed before reinstalling the gasket. Usually when removing the gasket it pulls the sealer from the side of the channel. All a-bodies 67-76 have this channel and most all leak. And No wiper seals won't fix it.

I have some bare body shells here I can get pictures of when the snow stops. They are in Trailers that I won't open to moisture.

Explaining it won't help without pictures. But there are drain holes that lead into the cowl from the lower windshield channel for a drain. These drains are open at both ends when one end should be sealed with seam sealer. If not they will empty into the car. Sealing the drain opening will only cause the chanel and trim clips to rust. You must seal the end of the channel that leads to the interior.

I just remembered there is a body in the garage next door. I'll get pictures of when I go retrieve my golf cart with the skid loader. I got it stuck coming home last night in the snow. Wait for the Pictures.
 
I discovered I had leaks in my front and rear windshields this past summer when my car got caught in a downpour on the way home from a car show. The windshields had been replaced, however they didn't have bedding and glazing compound installed around the windshields between the seals and the windshield openings. I removed the windshield trim and used 3M 08509 Auto Bedding and Glazing Compound https://www.3m.com/3M/en_US/p/d/b40067023/. There are many posting on FABO about this topic https://www.forabodiesonly.com/mopa...auto+bedding+and+glazing+compound&o=relevance.
3M must have stopped making 08509 compound because I couldn't find it in stock anywhere online. I finally found 3 tubes tubes of it at my local auto parts store, but nobody else had it.

20230801_163011.jpg


20230827_132155_HDR.jpg
 
This pic was taken under the right-side dash looking up and thru the glovebox area. I can’t gurantee that the cowling isn’t a source - but I worked hard a decade ago to seal that area. I butchered my firewall to gain access to the cowl area. I removed the pile of debris, replaced the cowels, and coated everything with fiberglass. I also put a stainless steel screen under the vent (in front of windshield) to prevent further contamination by leaves, etc. I’ve had to keep the car under cover for over 10 years because of this leak and I really need to fix it before I want to drive in the rain or park the car outdoors. This pic eliminates the windshield wiper source. Not sure what else it tells me.

IMG_0496.jpeg
 
Ken71Twister said:
This pic was taken under the right-side dash looking up and thru the glovebox area. I can’t gurantee that the cowling isn’t a source - but I worked hard a decade ago to seal that area. I butchered my firewall to gain access to the cowl area. I removed the pile of debris, replaced the cowels, and coated everything with fiberglass. I also put a stainless steel screen under the vent (in front of windshield) to prevent further contamination by leaves, etc. I’ve had to keep the car under cover for over 10 years because of this leak and I really need to fix it before I want to drive in the rain or park the car outdoors. This pic eliminates the windshield wiper source. Not sure what else it tells me.

View attachment 1716188989
Click to expand...
If you wait for the pictures I will show you where the water is coming from. It is not the drain from the cowl but to the cowl. I may do a video for you all. If you pile enough sealer around the windshield you'll eventually seal it. But did you ever try and remove the chrome from a car that had the windshield replaced and all slopped up with sealer like yours is showing? What a mess that is. But removing and original install from a car is very easy? Sealer is used to stop seeping not total leakage and constant dripping.
 
I look forward to the pictures. I’m not familiar with the drain to the cowl that you refer to. Sounds like I’m going to need to re-open the holes that I previously cut in the upper firewall. My previous repair is not pretty but it is screwed into place and removable (with some effort).
 
For what it’s worth - I’ve taken the water hose and run a heavy stream of water into the cowl area - going in thru the air vents below the windshield. No leaks. The leak occurs when I spray water the windshield (or let is sit in the rain).
 
A lot of people have good luck without using sealer, but the installation procedure in the FSM specifically states to use sealer "across cowl top panel lower windshield frame area." The installation procedure is actually pretty thorough in the FSM. As post #7 pointed out, the 3m bedding compound is what you want to use. Since it's no longer available, I'm not sure what a good alternative is these days.
 
I had to remove the trim and seal the windshield myself because the local glass installers I talked to didn't want to risk scratching the paint. It's a very messy job but well worth it. You have to keep checking for leaks and keep filling the openings until the leaks stopped. One installer told me I could try removing the inside trim and putting compound under the seal but I found that very hard to do and it didn't stop the leaks.
The guy in this video was able to stop a rear windshield leak without removing the trim . He used a product called Transtar 4167 https://www.tat-co.com/TranstarAuto...ish Datasheets/transtar_tds_4157.pdf?ext=.pdf.
 
Ken71Twister said:
For what it’s worth - I’ve taken the water hose and run a heavy stream of water into the cowl area - going in thru the air vents below the windshield. No leaks. The leak occurs when I spray water the windshield (or let is sit in the rain).
Click to expand...
Water doesn't flow up hill to the inlets to the windshield drains
 
Watch the video. One mistake on the video is that is not the cowl drain with the tape on it. That was taped up so the sharp edge wouldn't ruin any more shirts from my belly sliding by. That is where the fender attaches

 
Last edited:
Ken71Twister said:
I have a leak in my 1971 Duster - I’ve had it for many years and it is coming from the windshield on the left and right edges. I had a new windshield installed over 10 years ago by a local glass shop and it leaked after a year or two. I’m assuming they didn’t use the correct “stuff” around the windshield. I talked to a local restoration shop about pulling the windshield and re-installing with the proper sealants. They said the risk of breaking the windshield was too much for they to attempt the job. Is this a reasonable assumption? I just checked and it looks like I can replace a broken windshield for less than $500 - so maybe I’m willing to take that chance. Questions are as follows:
1) What is the correct sealant for the installer to use if the windshield is removed and re-installed or replaced?
2) What’s the chance that a good shop could apply sealant to the existing windshield and stop the existing leaks?
Click to expand...
If you plan on installing a new gasket, then just cut the old one with a razor blade box cutter and remove the windshield yourself. If you're keeping the old gasket and it cost more than a new windshield, try pulling the windshield and if it breaks, oh well, get a new one. I find using a wide putty knife and carefully peeling the gasket lip on the inside over the pinch weld to be the easiest way to remove the windshield without breaking it if you need to save the gasket. I like to start at an upper corner and work my way over to the other upper corner. Then work evenly on each side to gradually get to the bottom corners. Usually by that time. the glass with gasket will lift out.
 
It's around 4AM here and I'm winding down for bedtime at 5 (I work nights-up at 1PM to punch in at 3) by surfing the discussions about window molding clips for my '72 Duster and came upon this video. Promptly dropped what I was doing, marched past that sink full of dishes I was washing and straight out to the workshop and FILLED THESE HOLES!

THANK you OM for taking the time. I am NOT losing another set of floorpans to the "mystery leak" :thumbsup:

(this video needs to be pinned somewhere)
 
We had the same issue with the Dart this summer coming back from Carlisle. The water comes in the lower corners and as pointed out, when the cars were new Mopar used bedding between the seal and the body to stop these leaks.

The windshield was worse than the rear glass but both had issues. These will be a “to do” item while I don’t head out in the rain I have no real issue driving in the rain, except the bias ply tires…..

Cliff Ramsdell
 
Just took my windshield out today , notice urethane was on bottom of windshield , after cleaning all the urethane out on body notice both square hole were plugged, after inspecting I found it was not the urethane plugging the holes it was kind of factory sealer between upper cowl & lower the piece in the picture I remove from the vent hole under cowl, Both side so no drain on driver & passenger was leaking on floor include picture before & after . Note that piece of foam was inside Cowl

IMG_1585.jpeg


IMG_1586.jpeg


IMG_1587.jpeg
 
The small square drain hole must be left open to drain the windshield channel into the cowl. Otherwise the windshield channel will overflow and seap over the top. It is the side opening just in front of the pinch weld that needs to be sealed without closing the drain hole off. The drain must function. The opening on the side where I try and put the straw in must be sealed
 
I know what you mean will put butyl in to be sure ,did poured water in square hole would not not leak inside.
 
You must log in or register to reply here.
-

Back
Top