I was able to find quite a number of positive reviews for the POR-15 system when looking for a method to remove and repair all the rust in my FD fuel tank. However, none of the reviews online specifically mentioned how to address (remove, mask, ???) the plastic baffles like the ones found in the FD tanks. Is there a method I should use to avoid coating the plastic surfaces, which I presume will flake off into a pump clogging mess?

 

FYI you can buy a brand new gas tank for around $700 if you want to go that route.

 

POR15 is good stuff, I've used it on other rust restoration projects with good & lasting results. If you're going to restore the tank with POR15, your best bet is to just contact them and ask how to deal with the plastic baffles. They will likely need to know what kind of plastic it is made of to give you a definitive answer, and may suggest a few tests you can do yourself to determine what kind of plastic it is made of, but in the end I'd see two possibilities here. If the POR15 is compatible with the plastic and can fully adhere & bond to it, they will probably advise you to coat the baffles as well as the tank. Once the POR15 is cured/hardened to the substrate, it won't come off. If they tell you the POR15 is not compatible, and won't adhere/bond properly, they will advise removing the baffles if possible or masking them off before applying the POR15

 

Red kote is another option.

 

I did think about that option. I'm happy to put in the elbow grease and proper cleaning/drying/curing time to save the existing tank. Would be a shame to pitch it since it looks to be just surface rust on the inside, not pinholes or spots that have rusted through.

I also thought about putting together an aluminum box shaped fuel tank in the same way that the hot rod / kit car builders do. I have most of the tools to fabricate the tank, mounts, and weld it, but I'm not 100% confident on my welds being professional grade enough not to crack over time with vibration and sloshing. Price is attractive though.

I also tried calling several professional shops and they wouldn't do any restoration on a tank with plastic inside.

Finally, I did end up calling the POR-15 technical support people. They reiterated the warning that the sealant would not adhere to the plastic. My tech did made a side comment about surface prepping the plastic with 180grit and getting adhesion that way, though I'd still be concerned that vibration would shake the coating loose from the plastic on a fairly short timescale. Perhaps I should run an experiment and attempt to coat a cheap plastic Autozone oil drain pan that has been prepped with various grits using the POR-15 sealant just to see if it adheres. Though no telling what the makeup of the plastic baffle is I suppose.

 

Just make sure the baffles are intact. They tend to break off at the spot welds.

 

I like POR products too. Used on multiple stuff over the years, especially on an antique car. But I think you’re right to be wary of the consequences of coating the plastic. And I saw the pics of your tank, FP and hanger assembly.
I think I’d go with the new tank option. Or at least a good used replacement if it’s priced right and you could find one within a reasonable driving distance.

 

Warning.....we coated a tank and flake-off clogged the filter causing fuel starve...will no do that again.
If it won;t clean-up with solvent washes I would get another tank.
Clean used tanks go for $450-500.
Is this a street car or track? If track you have better options than stock tanks ( almost impossible to stop fuel starve with stock tanks short of running full).

 

It's a street car. It seems the cost of attempting the POR kit (either fully or just up to the rust solvent) and then having to replace it with another tank when/if it doesn't work is just a bit shy of the cost for a new tank.

 

The POR-15 kit has been great for me so far, about 6 months since finishing. Before starting the process, there was a ton of surface rust. I talked to the company about the plastic baffle that sits below the fuel pump and they said it needed to be removed before sealing the tank. The baffle came out without breaking with some heat and some bending. It also went back in without too much issue. If you have any questions about it feel free to PM me.