seaguy said:
Search for "Caswell Tank Liner" . That is what folks on here recommend. I must do the same eventually. This is supposed to be best for the Fiberglass tanks.
I had Caswell fail on my fiberglass tank. I had to replace it with one of those Pakistani reproduction steel tanks. I replaced my tank before this junk did any more damage.
I've seen this product fail on at least three other occasions over at Wes's shop - One was a '72 Interstate, which required rebuilding the carbs and a new steel tank (repro Interstate tanks are not cheap!), One was a '71 Roadster which required replacement of the tank and replacement of the carbs, and one was a Tiger which, while it had a steel tank, a PO had lined it with Caswell.
Each of these 4 failures had the same symptoms - the ethanol would soften the liner, and this liner would expand, bubble, crack and peel off the inside of the tank. The liner, when pieces were fished out, would look and feel like old latex. When left out to dry for a day or two, these pieces would harden back up. The three bikes that ran with this condition had another symptom. The dissolved liner would redeposit in the carburettors, intakes, and valves, leaving black droplets that looked like burnt plastic or sugar. On one of the bikes, these deposits caused the slide to stick in the body. The gas also turned cloudy when this stuff was in solution, almost like a Weissbier.
Mike Caswell said he would send me some extra strong sealer to redo the tank, but it never happened. The tank is occupying the top shelf in my garage.
My advice to anyone with a 'glass tank is to not put any ethanol-containing gas into it. I understand marine gas doesn't have ethanol, but haven't verified this. Another option would be low-grade racing fuel.
This ethanol situation isn't only damaging classic vehicles with 'glass tanks. Acerbis, who supplies tanks for Ducati, has also had warranty issues due to ethanol.
