Corrosion on the aluminum windshield frame.

[BrianK82]

I was wondering if anyone had any good repair information on this. I spent two weeks looking at used CS verts. before I got mine and everyone of them had this issue to some degree. On my car, it's only on the drivers A-pillar. Does this piece come off, and if so how? What is the best method to remove the corrosion and to keep it from returning?

[GOT2B GM]

have them sandblasted and powdercoated, I just had it done on my CS vert.

 

[BrianK82]

Wow. That looks great. How much did that run you? Also, how do those pieces come off. I just picked this car up yesterday so I haven't had time to acquire the factory service manuals yet, so any help is appreciated. Thanks.

[GOT2B GM]

you need to remove the interior windshield frame trim first.

 

The Latch pocket trim, sun visors are removed in order to remove interior trim.

 

Then the rubber A pillar seals are removed.

 

There's a screw at the top and three at the bottom holding the seals in. (each side)

 

Then remove the 5 screws holding the seal retainer channel to the A-pillar (each side)

 

Then there are a bunch small phillips screws holding the 3 trim pieces in place.

[STGBROOK]

i dug the old bulletin out of the system for the paint process for blistering reveal moldings. this procedure works well but i like the powdercoat. looks real good. at least you have an option. copy this bulletin and bring to the local paint shop if you decide to go this way.

 

#93-T-77: PAINT BUBBLING/BLISTERING ON WINDSHIELD REVEALMOLDING - (Jun 24, 1993)

SUBJECT: PAINT BUBBLING/BLISTERING ONWINDSHIELD REVEAL MOLDINGS - REFINISH WINDSHIELD REVEAL MOLDINGS

MODELS/YEARS: 1990-93 CUTLASS SUPREMECONVERTIBLE

CONDITION:Some 1990-93 Cutlass Supreme convertibles may exhibit bubbling/blistering painton the windshield reveal moldings.

CORRECTION:Refinish the windshield reveal moldings using the following procedure:

1.Wash the windshield area and reveal moldings with soap and water and wipe dry.

2.Unlatch and lower the convertible top.

3.Clean the reveal moldings with a wax and grease remover.

4.Mask the windshield pillar weatherstrips, retainers and inner finishing lace onthe reveal moldings for protection during the sanding operations.

5.Sand the reveal moldings to the bare aluminum using #320 grit sandpaper.

6.Clean and prepare the surface with aluminum cleaners and conditioners usingproducts such as *DuPont 225S followed by 226S, *PPG DX533 followed by DX503,or equivalent.

7.Remask the molding areas for priming and paint. (Protect all areas notrequiring paint).

8.Apply a coating of self-etching primer such as DuPont 615S/616S, or Epoxyprimer such as *BASF DE15/DA16/PR70, PPG DP90/DP401, or equivalent.

9.Apply 2-3 coats (or sufficient amount for hiding) of Black Single StageUrethane paint following manufacturer's directions.

10.Following air or force drying, remove masking and raise convertible top.

[j_mezz]

Be ready for a challenge though, at least some of those screws will fight you tooth and nail on comming out!

[GOT2B GM]

on a northern car they definately will

[gryfan]

have them sandblasted and powdercoated, I just had it done on my CS vert.

 

matt,

nice work. that is going to look great on a black car.

cheers,

gryfan

[STGBROOK]

matt how much did it cost to have the pieces p/c.

 

thanks,

brook

[GOT2B GM]

I had 3 cowl pieces done (one for the vert, one for my TGP and one for Nunzi's Z34), and the 3 windshield frame pieces done. $300

 

The $$ was in the cowl pieces because they had to be hand stripped and sanded (labour intensive - pieces are too thin for the sandblaster , would warp)

 

To just have the upper 3 windshield frame pieces done I would've been under $150

[STGBROOK]

thanks, not to bad. i think i'm going that way instead of paint.

[RA4SPD]

The corrosion is caused by electrolosis..two disimilar metals touching cause the issue. The body is steel and the moldings are cast alluminum. You need to remove the interior trim along the A pillars as well as the top interior header panel. Once removed you can access to the mounting screws on each piece. You will need to remove the A pillar molding first. It is held in place by 12 screws. You must first remove the A pillar weatherstrip. You can pull the weatherstrip out starting from the top or slide it out by carefully pulling up towards the roof area. It should slide out relatively easily. Becarefull not to tear as these are not available anymore from GM. Once removed you can access the phillips panhead srews that attached the weatherstrip channel to the A pillar. When you remove this you will find a sticky tape (looks like Byuetal tape) that seals the track to the A pillar. It is about 1" wide and is attached to a mylay backing. You will need to try to save this tape as it provides water tight sealant as well as sound sealer. You can now access the 6 counter-sunk phillips head screws that hold the molding on. Some may be rusted so be prepared to drill some out if the heads strip due to rust. They are somewhat difficult to se so be careful that you have removed all 6..they are there. Do the same on the other A pillar. You can now remove the phillips head screws along the top winshield trim. There are numerous screws so you need to be sure that you get them all (some visible and some through access holes in the header) . Once removed you can pull up on the molding. It may stick to the windshield but with a little effort it will eventually pop off. Be carefull not to pry on the winshiled to remove it or you will crack your glass. There is also some closed cell foam weatherstrip along the header and A pillar for noise reduction. Due to the age it may be dry and brittle. It is not available from GM. You can buy a similar product at your local home improvement store as a good replacement. The originals were impregnated with an asphat type substance. Once removed carefully look at the mounting studs on the trim piece. Since these were conversion cars they shimmed the molding with small washers at all the mountings studs...they sometimes stick to the molding studs or stay on the header frame of the car. Onceyou have the 3 trim pieces removed I suggest that you have them media blasted. There is a lot of adhesive and glue from the factory that will need to come off. They will then need to be Epoxy sealed prior to painting. I recommend taking them to your local body shop for epoxy primer and ppainting. Since these are black you will see any imperfections so spend the extra money..it will be well worth it. You can also get them powder coated but you can not expoxy seal them and the Black may not match the rest of the exterior black trim. Installation is revered as removal. Note: You may need to make your own Byuetal tape since it is not available from GM. You can purchase a roll of Byuetal from local parts stores. You will also need some mylar cut into 1" strips. You can cut the tape and strips to lenght then roll the Byuetal out with a rolling pin. You will need to make sure the Byuetal is on one side of the mylar and a wax bases paper is placed over the tape prior to rolling. Byuetal is very stick so it is critical that you get a non stick back paper. Roll out to about 1/8" thickness or as close to original as you can. The prosess of removal and reinstallation is time consuming but well worth the result. Good luck!