POR-15 and battery acid

[Tut]

When waking my car from its winter slumber to begin to get ready for its first DE I found some fizzy stuff at one end of my battery. The battery is out, the gas tank will come out this weekend, the new gas tank seal is on its way. I have the baking soda to scrub everything out. I'll be getting an Optima. I've seen the threads regarding the Optima mounting plate.

The paint is bubbled only in one area. Do I need to take things down to bare metal and then treat with POR-15 only in the area where the paint is bubbled, plus a "safety margin" around the bubbled area, or do I need to strip everywhere I see any evidence of where the acid was?

Thanks.

[Tut]

bump

[karleick]

I've got the same problem and plan to tackle it with POR 15 soon. My additional concern is the area in the enclosed space under the battery tray. I can clean it with soda and wash and dry it, but am unsure how to proceed with the POR 15 prep and application. I'm following this thread with interest.

[Porsche-O-Phile]

I've always just use their "metal ready" stuff (basically phosphoric acid) to etch, wipe clean and paint the stuff on. Never had any problems.

[jcarpio]

I recently did my battery trays with the POR-15 starter kit, includes metal ready, POR-15 in your choice of color, a brush and some rubber gloves. It will give you good instructions. Essentially you clear off all the bubbly paint, then use metal ready on the rust/corrosion, then paint over with POR-15.

[Formerly Steve Wilkinson]

The most important thing with POR-15 is to either paint over rust, so it gets some tooth, or scrupulously clean the area. Otherwise the POR-15 will eventually just come up in a big, strong, neat sheet.

[Ray B]

+1 on the phosphoric acid for rust. If no rust, then baking soda and rinse. I use a light grey paint over previously rusted spots so that I can moniter the area. The only problem with POR is that after you put it on, you never know what's going on underneath.

[Porsche-O-Phile]

True, though the theory is that once it's encapsulated it's sort of in stasis forever. One hopes.

[Ray B]

Please Jeff, no fancy words around me (stacis) -I'm a dumba$$ EE. "One hopes" is the operative.

[Tut]

karleick:

The area under the battery tray is a problem. I guess we clean it as best we can with baking soda, rinse, and then prep and paint what we can reach (not much under there).


What I'm getting from the rest is strip, prep, and paint just the bubbled paint and the area surrounding it. Can you put a color coat on top of POR-15?

Thanks, folks.

[Formerly Steve Wilkinson]

Rust Never Sleeps. And yes, you can put anything you want on top of POR-15.

[petrolblue83911]

Neutralize the acid first, give it a good rough cleaning-ie to get any loose dirt/dust, and then POR over.

POR 15 will not adhere to surfaces if it is contaminated with brake fluid for example, but after cleaning it should be fine.

[Porsche-O-Phile]

OK

Just don't start talking about load distributions and NEC requirements around me either. I'm just a dumb architect.

Anyway I think the theory behind the POR-15 stuff is that once applied it creates a moisture-proof seal that I believe is also impermeable to oxygen (it's an epoxy paint essentially). This means the metal underneath cannot oxidize/rust/corrode. I think that's the theory anyway - there's a description of it (kinda' general) on their web site. Maybe a chemist would understand it better or be able to communicate it better, but I believe that's the theory.

[Ray B]

That seems logical-no oxygen, no rust. It must work OK or we'd be hearing about it. I guess the easiest thing to do is not buy anything that is rusty. The area under the tray is a PITA to get to. I have painted with a WD-40 type nozzle/straw with good sucess.