Seam sealer and POR15
 

I'm going to POR15 the area under my back seat while I have it out and replacing my top pump. Do I need to remove the seam sealer before I do this?
I assume a good wire wheel will remove it. It's hard stuff though. Kind of hate to remove it.

I Por15'd my gas tank years ago but if i recall they will want a clean surface and you are supposed to use their metal ready product before application.

When I did the windshield frame I removed all the trim inside and out and then got all the old butyl removed. Decreased and the metal prep and two coats of POR.

I was wondering if anyone had gone over the top of the sealer and if it peeled or flaked off. I don't have any rust at the seam. Just light surface rust in the bottom of the pans .

I guess I can paint up to the sealer and over the factory paint

POR 15 sucks...way to much prepping.

SEM has a product called Rust Trap...which will go ovah bare metal...without all the crap you have to go through with POR.

Leave that seam sealer ...and just go ovah it with some SEM 2 part seam sealer...let it dry over night ,,,then apply 2 coats of rust trap...30 minutes in between coats

Is the area under the back seat bare or rusted metal with no paint? POR15 is designed to go over bare or rusted bare metal, no paint or other coatings like seam sealer, it will eventually peel off & provides no added protection over another coating. POR stands for paint over rust, its best to a clean but rusted surface, otherwise as mentioned it requires lots of prep & etching of bare metal.

I would look for another product like the SEM mentioned or other rust neutralizer then a coat of good paint.

I used Rust Bullet as it can go over and stick to both unpainted and painted. I coated the underside of my 55 Chevy with it and left it that way. Nothing has peeled off or any surface rust shown through in almost 15 years now. I also used it in many areas on my 72 Lemans vert when I restored it.

If you already have the POR-15 just prep as well as you can and paint over the seam sealer.

What’s it gonna hurt?

I’ve used it on rusty trunk pans and floorboards with great success, even over some painted surfaces and it hasn’t peeled.

After more than 25 years since applying it it’s still doing just fine.

Are there better products, probably but I haven’t had anything like peeling or any kind of failure using it. I’ve used it on front frame rails that weren’t terribly rusty, a core support that had been chemically dipped for rust and paint removal and an entire front suspension that I bead blasted clean and it’s been great.

You could paint over seam sealer or dig it out. I dug out and wire wheeled all seam sealer in the trunk and filled with a liberal couple coats of por 15. Seam sealer was a fast and dirty way for the factory to seal the joint. A lot of times they smeared too much on. After 50 years it gets hard and shrinks and let's moistior and rust under it. I got a cheap wood chisel set and it takes it out real quick by hand, then wire wheel, por 15 and it will seal it up permanently. Unless you are doing a show car.

Since we don’t have a picture of what you’re actually dealing with it’s hard to tell you what might be okay to do or not.

Obviously if it’s crusty near the seam sealer you should remove it. If it’s looking good in that area it’s probably okay to leave the seam sealer alone.