TechCam97

iTrader: (5)

I would do it to be safe.

RPM WS6

iTrader: (3)

I agree with the above post by TechCam97. The TSB calls for use of the primer even with the referenced adhesives - so it's definitely advisable to use it.

FASTFATBOY

iTrader: (23)

I recently pulled two of these with this kit http://www.harborfreight.com/profess...kit-96339.html

Removed the t tops but not the hatch.

If you take the piece that looks like a knife and stick it in both sides every 2 inches and swing it side to side prior to using the wire it makes the job MUCH easier. I did this all the way down both sides. I would sharpen both sides on a grinder before I left home with it.

The worst part is the vertical sides, the most glue is here. I took a big sharp knife and used it to cut some of it loose.

FASTFATBOY

iTrader: (23)

I am about to do mine, is 2 tubes of the 3M adhesive enough to get the job done? The tubes are not the same size as a regular tube of caulk they are only 10.5 ounces.

ZexGX

iTrader: (28)

So the painter at the shop I had lined up is now refusing to epoxy primer the underside of my carbon roof, saying he doesn't want to be responsible for adhesion issues when installed on the car. I am providing an Eastwood Epoxy Primer. This is the underside of the roof. Is his complaint valid?

ZexGX

iTrader: (28)

Attached is a clean PDF of the original GM TSB, made from GM Techline eSI. Everything is clear and easy to read. If this is a copyright issue, feel free to delete this post... Otherwise, it would probably be a good addition to the first post.

RPM WS6

iTrader: (3)

Deletion of the epoxy primer seems to be a primary reason for the bubbles in the first place. The TSB specifically calls for this primer on the underside. I don't know anything about the CF roof, but the OE-material roofs should have this process done according to GM.

I've included a link to your post in the first post.

Auto Recon

Ok, so thankfully I found this forum about a month ago.
Back in Nov '14 I paint the roof on a 2002 Firebird not knowing that there were issues with the roofs on these cars. In Feb the customer brought it back to me saying the paint was still bubbling. I proceeded to sand down below the bubbles when I realized the roof was fiberglass. I had previously assumed that it was metal since magnets stuck to it. So once I did a search for fiberglass Firebird roofs I came across this forum and found out why the paint bubbled. After about 2 weeks of trying several different ways to remove the donor roof without breaking it I finally removed it from the roof frame where the junk yard cut it off. On the customers roof I just went to town with a linoleum knife and 3" cutoff wheel and cut around the inside of the glue. Figured it will be easier to cut through the urethane with majority of the roof gone.

Now to my question. Does the windshield molding have to be removed to cut the front urethane off? I have read that some say there is no need to remove unless it is already damaged or dry rotted. Thanks

OhTwo

iTrader: (13)

I didn't remove any weather stripping when I did mine. I removed the center section trim piece for the t-tops which goes over the new section after it is installed.

Auto Recon

Forgot to mention the Firebird is a hard top.

Jimbow

Just curious if any of you guys have tried to use a barrier coat? It's used in marine applications for a primer coat between fiberglass and bottom paint. It's really tough stuff

It protects the hull from getting blisters from sitting in the water, it can ruin the bottom of a hull if it's not applied.

I'll be painting my car in the next few months, I'm gonna try the barrier coat method first, just as an experiment. And if the roof bubbles again then I'll replace the panel.

I'll be doing all the paint and bodywork so it doesn't cost me any money in labor, so no money is really wasted, just my time.

RPM WS6

iTrader: (3)

I think the issue is that once the glue has worked its way into the panel, no amount of coatings will be enough to prevent it from continuing to be drawn out by heat/UV exposure. When the epoxy primer is properly applied under the panel, then the glue isn't able to seep through in the first place, thus the panel itself becomes the barrier from heat/UV getting to the glue. I don't think anything short of the thickness of a new panel (coated from the underside) is going to stop the continued progress of this glue from escaping since the panel is already saturated.

But if your method does happen to hold up long term, please report back.

SparkyJJO

iTrader: (11)

Which way is the pressure? Water > barrier coat > hull. Barrier coat is pushed onto hard surface.

We have the opposite problem. Glue ooze is pushing out from the hull (roof), to open air. Enough ooze pressure and the coating, without anything hard to hold against, will likely bubble and pop.

Feel free to try it, but I highly doubt it'll hold up.

Jimbow

It's used not only where the hull would be I. The water, But also on hull repairs above the water line.

What you said makes sense tho, and honestly I didn't think of it that way.


I'm gonna give it a shot and if it doesn't work I'll just replace my hardtop, not a big deal either way.

Dan

iTrader: (1)

I talked to a reputable body shop yesterday that re-painted one of my friends cars with a bubbling sail panel last year. I warned all parties involved before he painted the car that sanding & painting will not fix the issue. I guess no-one listened to me because the bubbles came back a week later. BUT the body shop claims it's the panel itself & not the glue, due to the temperature the car endures. He said it has happened to all F-bodies. I told him, well bud I have a 98 & 99 Trans Am & have no sail panel bubbling issues(Yet), he didn't know what to say other than if you keep the car in the garage it might not happen(Like I never expose my car to the sun)I think he is wrong. So is it positively the glue or the panel itself?

TechCam97

iTrader: (5)

In a nutshell: both. GM decided to cheap out during the mid 98 production and stopped priming the underside of the panel. The glue was then able to seep through the panel and appear as the bubbles we hate so much. That's the reason that 93 - mid 98 did not bubble, the bottom side of the panel was properly prepped and a barrier was there to stop the glue from seeping through.

SparkyJJO

iTrader: (11)

My 98 was never garaged. That panel was spotless aside from some scratches and such.

My 99 was garaged most of its life, with a couple years it wasn't. It is covered in tiny little bubble zits. Stupid me didn't think to try to keep the panel off my old 98, it was even the right color too!

I'm not the only one who has had a 98 or older with zero bubbling issues. That guy's claim that the panel itself is to blame is wrong.

RPM WS6

iTrader: (3)

This is exactly correct. This "body shop" guy doesn't understand the scope of the issue and seems to be making assumptions. If he claims they "all do this", I'd like to see him show us some '93 thru mid-'98 cars will bubbles. He won't be able to.



My '98 was built on 3/23/98, and doesn't have so much as a single wave or bubble. Yes, it's garage kept but it has spent countless hours sitting in full summer sun at car shows and events over the years, so it's had plenty of exposure.

I know exactly what the issue looks like in the early stages as I watched it happen on my '02 car and have been investigating this issue for over 10 years. GM starting making the change around May of '98, so some of the May/June/July '98 cars are hit-or-miss, and the closer you get to the end of '98 production the more likely you are to have a "problem" car. April was a low production month so I don't have a ton of data but so far no April cars have reported bubbles. March and earlier seem to be definitely safe, using my own car as a primary example of a late March build that has had plenty of sun exposure and not a single issue. My '02 car was already bubbling by 2007, but after 17 years in the same climate my '98 has yet to bubble.

Dan

iTrader: (1)

Thanks for the reply guys. I even mentioned the 93-97 cars didn't have an issue. He said they started to use a different material for the panels after 97.

RPM WS6

iTrader: (3)

He is not correct. Early and mid-'98s have no issues. The process change took place beginning around May of '98 and was fully implemented by the start of '99 MY production.