Epoxy primer over original seam sealer?

[MajorPIle]

I'm restoring a 73 bug and I'm not having it dipped or sandblasted, and I'm not planning on stripping it down to bare metal.

I'm just sanding where needed, and using a wire wheel to get rid of rust (and a rust converter for any pits with rust).

I'm working on the inside of the trunk so there are a lot of small areas and it's not easy to get tools in there to strip everything down, including the original seam sealer.

I bought Eastwood epoxy primer in their spray can, and I plan to paint the inside of the trunk with this.

Will I have any issues if I leave the original seam sealer in (which appears to be fine) and spray epoxy primer over it?

[viiking]

Yes.

There is no guarantee that there is no rust under the seam sealer.

Here's a photo of my original 68 with the seam sealer removed. It was totally rusted underneath and showed no signs of external damage at all.

Of course yours may be ok, but you won't know if you don't look.

_________________
1968 1500 RHD Lotus White Beetle since birth. In the hospital for major surgery
1966 Lancia Flavia Pininfarina Coupe - in the waiting room
Discharged: 1983 Vanagon, 1974 1800 Microbus,1968 Low Light,1968 Type 3

[2type2]

Everbody,relax and investigate.How about a little test surgery first!? Find an area(s) that looks suspiciously like it would/could/has seen moisture.Get after it with your putty knife and look underneath the seam sealer to determine current condition. If you feel lucky,that is if things look acceptable, just reseal that area and proceed. If not, well you have work to do.
On bare metal, phosphoric acid is your best friend(Ospho). Whether your car has these seam issues is dependant on its past environment. The frailties which remain after refurbishing are greatly affected by future exposures:(garage or curbside parking?) So it's an individual assessment. Remember that seam sealer flexes, so painting over sealer will not assure a waterproof seal when the paint cracks.
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"A life of peace and happiness depends on your own gratefulness"

[MajorPIle]

[scrivyscriv]

[Busstom]

Pile,

If you bought Eastwood's epoxy primer in a rattle can, then you must have (or should have) reviewed the extensive Q & A's associated with their product lineups. In my experience in researching their products, most all of their primers are supposed to adhere to THEIR seam sealer products, but they can't assure you that their primer will stick to OTHER seam sealers.

So in your situation, if you're set on spraying the epoxy over some of the existing seam sealer, my suggestion is to clean it (the existing seam sealer) as best you can (like with Simple Green or a cleaner of your choice), then scuff it good with some coarse Scotch-Brite, then clean (wipe) it thoroughly with acetone. This should give you the best fresh substrate on the old seam sealer to have a chance at success. Besides, you're not building a show car, so who cares if the primer/topcoat cracks or chips at the seam sealer? The only way to almost guarantee success is to start from scratch.

With respect to what MAY lurk beneath the old seam sealer is a completely different question, I have no argument or input on that point. So just go for it and do it, it's your car. By the way, I see your "rust assessment" thread and it looks like you're on the path to doing things right. Maybe start a build thread and consolidate all your issues and progress in one place.

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My name's Steve and it's pronounced "Bust 'em" (cuz people think I'm Tom) 😏

[viiking]

I think paint will stick to the old seam sealer better than any new seam sealer. New seam sealer still off gases for a fair while resulting in shrinking which may crack paint. But two pack epoxy is pretty tough.

I replaced my seam sealer on the sections like I pictured above with new sealer. I painted the seam sealer with polyurethane paint and it did not crack. So
I guess epoxy should be ok too.
_________________
1968 1500 RHD Lotus White Beetle since birth. In the hospital for major surgery
1966 Lancia Flavia Pininfarina Coupe - in the waiting room
Discharged: 1983 Vanagon, 1974 1800 Microbus,1968 Low Light,1968 Type 3