Fumes leaking through gas tank??

[jason0779]

has anyone ever painted there plastic gas tank? I just got done rebuilding a 250R and I used all black plastics except for the gas tank. I used a plastic primer, and put on a couple coats of black followed by several coats of clear. It looked great and seemed pretty durabale but then yesterday I went out and was moving the threewheeler and I noticed it was lifting a little and had a weird texture look to it on the bottom. The area where it was lifting/textured was exactly where the fuel level was. Everything over the fuel level looked normal. Could fumes be seeping through the plastic pores??? any ideas??

[coolpool]

You guessed it, the plastic that you painted will not hold hold its look for long. I have read on here that coating the inside with POR15 or KREEM before painting will solve this issue. Too bad about you hard work. Search around the site and you will probably find someone in the same situation.

[just ben]

I lined a tank with northern brand tank liner and painted it with base/clear over plastic primer. This was 6 months ago. No paint lifting or bubbles yet.

[willreed03]

It's true a plastic tank will 'breathe' the gas vapors out causing the paint to lift and bubble. That is also why you see some decals on the plastic tanks that have little holes punched in them, it's to let the vapors out so it won't peel the decal off. You need to line the tank to prevent the vapors from breathing out and bubbling the paint.