The Stovebolt Site Forums The Shop Area Paint and Body Shop Trouble with Cowl vent installation......

Ok so Im on the final assembly of my first full restoration of a 1950 GMC and Im stuck at the cowl seal......

The problem Im having is that I attempted to glue in the front portion of a new rubber cowl vent seal in its channel using 3m weather strip glue and after letting it dry for a couple days, the seal pulled right off the glue with ease. ate up the paint in the channel pretty good but didn't bond to the seal. I washed the powder off of it with mild soap before hand too. i believe i will have the same issue with the side cowl vent seal as well.

Any suggestions?

What weatherstrip seal did you use.

3M weatherstrip seal is applied to both surfaces (rubber seal and painted body panel). After a short wait for tack-dry, the two surfaces are put together.

Was the metal under the seal rust-free and clean before it was primed? What primer was used?

The word "glue" instead of "adhesive" rings a bell. I wonder if you are using the
3M "Super Weatherstrip and Gasket Adhesive".

Also, what material is the gasket?

Well you are correct in that im using the 3m super weather strip adhesive. the material is rubber not foam. the original channel was treated with rust killer, painted with por 15 then primered and base coat/clear coated. the adhesive ate up the base/clear pretty good. the issue is the adhesive didnt stick to the gasket at all. i peeled it right off like a mold. I wonder if super glue is gona be the trick.

Another question, how do you guys apply it normally? i believe i placed it on kinda thick directly from the tube. will try a small brush next time. I also did coat both surfaces and wait for tack.

,,,,, not trying to be a smarty here but wonder what the 3M company would say if you called them, Marc? Something sounds amiss to me as I have used the same stuff with good results....but maybe fortunately not on finished paint.

Whatever the cause I'm curious as to what happened!

Me too as I will be doing the same thing in a month or two.

I wonder if you put the adhesive on too thick. I always heard to apply a thin coat and let it dry a bit before contact.

I've had to clean new rubber w/thinner to remove the mold release before gluing it.

you might try to use the modern day windshield urathane type glue they put it right on painted parts and set the glass into it,I use it for what your trying to do but what I do is ciean rubber seal off with alcohol pad /rub it over cowl once /dont let the paint stay wet apply glue on one part and press into cowl I stoped using the trim glues years ago because they will eat into paint you can ask at auto parts stores about it, You can even use it to glue your door glass to the to the chanel stuff holds good, door rubbers to

What is mold release?

that is what they use to keep the rubber from sticking to the mold when made/it stays on the rubber when they take the part out of the mold.you must clean this off before you glue in place

Did you clean or dress the gasket before you tried to glue it on? If yes, what type of cleaner/dressing did you use?

Also, what base-coat/clear-coat paint did you use?

I have to agree, that windshield urethane is some really good stuff. Just give it the correct dry time.

That's your problem. Clean it with lacquer thinner and try again. I have the same seal.

BTW, there are two seals available for these, one is rubber like the original and the other is foam. For anyone reading this, don't bother with the foam ones, the vent won't sit flush with the cowl because the foam is too thick and stiff.

so... who makes this windshield urethane?

My local Oreilly Auto carries 3m8609 on the shelf.

Check your local FLAPS

Good Luck

Will this work on weather striping?

I did not use it for my door weatherstrip. I used the 3m product in the red tube.

I do plan on using the 3m8609 on my windshield.

I cannot review it because I havent used it yet.

The 3m8609 has been recomended to me buy the glass guy who cut my door class.

I was just providing a source for urathane sealer.

I have not glued my cowl seals yet. Maybe I should since Ive started driving the truck more.

Perhaps I should start a new thread on this.
I have a tube of:
Permatex Ultra Black RTV Silicone Gasket Maker PX# 82180
3M Super Weatherstrip and Gasket Adhesive Yellow
Napa Clear RTV Silicone Rubber Adhesive Sealant
Loctite Black Weatherstrip Adhesive #37532
Will any off these do the trick?

Does anyone have experience in what works best for weatherstriping.

I believe only fools refuse the voice of experience. I don't want to use any of this stuff without knowing for sure it's going to work. I don't like do-overs and this do-over would be a lot of work.

All I ever use is 3M yellow weatherstrip adhesive.

I used the 3M yellow for my cowl vent seal, side window track install, and fender / body gaskets. Worked good in all cases. You must have a contamination issue on your seal ?

Well the stuff did eat into the paint that's for sure. So from the responses I believe I need to rewash the seal because I only used mild soap to wash it, highly diluted aswell. Never thought of it having mold release on it unless the mold release is the white powder that came on it. That I did get off. I also probably put the glue on to thick. The stuff came pouring out fast so it was hard to prevent. Next time I'll try using a small brush to apply a thin coat. Ill keep ya posted on all the trials and tribulations seeing as I have the entire suburban to seal with new rubber. Sure hope the foamy door seals go better. They should take to the glue better I suppose.

Thanks for all the help guys!

3600 yes what you have will work don't use the yellow 3m im not sayiny its bad just not on this part any 100% silicone will work use new tube, not one that has sat for a long time unopend or bin opend for a while.I had some not dry good if it was old or opend for awhile, the drying agent evaporates Dont gob it on,a nice 1/8 to 1/4 inch beed is fine, press rubber in place.You can hold in place if need be with tape a few strips here and there. the silicone will not eat into the paint like some glues do but you MUST clean up any silicone right away with a wax and grease remover not something that will eat into your new paint good luck

Well cleaning it with acetone seemed to work. Thanks for the help guys!

A spray type silicone.