Stripped my cockpit down to the glassed floor, pulled the fuel sender and discovered a pile of rusted crap and what looks to be some aluminum corrosion. Pumped it all out in to a coffee can using an electric pump with filter. Once I got to the bottom I found a little yellowish scab looking material, that I scraped off, while scraping off this material I uncovered 4 or 5 pock marks about the size of the head of a ball point pen. I believe it's from pieces of the sender rotting off and attaching to the tank and continueing to corode. None of them are through the tank but the ittank is pretty thin wall .090, I believe ( still have to put callipers on it).

Going to pressure test the tank because I ran my camera in it and it looks great and the deck looks great but I'd like to seal up these couple pock marks so it lasts a good long time. After doing a lot of reading I found nothing on here about tank repair materials but I did find POR15 for gas tank repair
https://www.jegs.com/i/Perma-Cool/771/49216/10002/-1?CAWELAID=230006180039264274&CAGPSPN=pla&CAAGID=4 4693592161&CATCI=pla-191844202151&CATARGETID=230006180039217633&cadevic e=t&jegspromo=nonbrand&gclid=CjwKCAjwyrvaBRACEiwAc yuzRKyZGLV4JnJJa5XFe5vRgzkzGk-Un484eMFmKMZzkLQpUiwmUi2DixoC3w8QAvD_BwE
and
Caswell platings gas tank sealer
https://www.caswellplating.com/epoxy...nk-sealer.html

Does anybody have any experience with either of these or something better for inside the tank submerged in gas and ethanoyl?

I figure each pock mark would require a .15" to.25" circle to seal over them.

Ayuh,..... A New tank,.....

If that's on the inside I would think there is issues outside, more so if there was any moisture against the outside of the tank. This is the outside of mine when it was removed. I replaced with new

https://forums.iboats.com/filedata/f...9&d=1418667687

I've never used Por 15 inside a tank but have done a couple of frames with it and probably won't use it again. It flaked off in many places and actually held moisture around brake and fuel lines.
there are linings that can be used but you would have to send tank away. Might be easiest to have a new one built....

Well I pressure tested it and it held 2+ lbs for over 2 minutes. I also mic'd the tank and it's .120 wall thickness. I also took some 1/16 aluminum welding rod and the deepest hole measured .030
deep so I think it's good.

Again I really don't want to cut the deck out because it's in really good condition and at this point I think I'm going to leave it.

Thanks

It ought to be a crime to install fuel tanks in such a way that they're not easily accessible and easily removable !

I have and had the same flaking where the fuel lid closed the neck (motorcycle). That was even before installing the lid!! Followed directions to the Tee.

The only thing they're worried about it is making it through any warranty period.

I'm installing a new sending unit in the tank, i have a new cork gasket so what do you recommend as a sealer for the gasket to the tank and sender to gasket?

I'm thinking 3bond 1211, any other reconditions for something that's fuel proof?

Thanks

I would just used the cork gasket and no need for sealer.

It is not smart to pressure test the tank unless it is a very small tank, it puts to much stress on the tank. Multiply the side area by the test pressure to calculate the force applied.