Painting plastic fuel tanks

[Toominibikes]

I restored my brothers Bird minibike for his 50th birthday 4 years ago. I prepped the tank like the paint supplier told me to and it still pealed. I used single stage paint. It turned out perfect, but it pealed. I painted a Heald tank with a spray can an that has not pealed at all. I want to repaint his tank and asking for some suggestions.
Thanks
Scott

 

[Spyderdregg]

I did all the prep and used fuel resistant engine paint on my MTD but the first really hot day we had this past summer all kinds of bubbles showed up in the paint so Im not sure what works but Im really interested to find out :laugh:

 

[mckutzy]

Some paints need a kinda plastic prep solvent primer. Im not really sure to what.

Bumpers(caps) are painted according to what plastic they are made up of.
Im going to guess the tank is a PP or PE. So painting will be a pain if not at all.
Im thinking your approaching automotive territory.

 

[Havasu Dave]

There is a theory going around that plastic sweats, or otherwise exudes fuel vapor. If that's the case, we'd all have paint falling off of plastic tanks eventually.

For painting plastic, there is an additive that allows more flex in automotive paints. I doubt any tank flexes enough to warrant that.

Any scratch or nick in the paint that allows the smallest amount of fuel intrusion will result in bubbling up.

While catalyzed acrylic single stage should work, I haven't had a lot of luck with them on gas tanks. Urethane clear, two part catalyzed is the only thing I have had luck with on gas tanks.