That's pretty much the same as I found when I pulled my tank out of the County. I used the POR15 Tank Sealer on the inside as directed. On the outside, where there were any decent sized holes (up to a few mm) I first used some 'Knead-it' putty (that two part putty designed for emergency repairs to fuel tanks, radiators etc), then used the leftover POR15 Tank Sealer on the outside, including over the top of the putty. I also cleaned all surfaces, inside and out, including the stone guard, and treated everything (bare metal) with POR Metal Ready (all the POR products seem to be good stuff), then primed and painted. I finished off with some clear 'stone shield' on the bottom half of the tank and, importantly IMO, sealed the gap between the stone guard and the tank with silicone or similar to keep the dirt and water out, which was the problem in the first place.
That was about 2-3 years ago and all is still good.
Cheers, Murray
Before and after.............

Bookmarks