Skorpion fuel tank paint blistering

[ralf]

Oh dear, my Skorpion fuel tank has broken out in blisters. I’ve had the bike since 2001 without any suggestion of this problem until today, so why now? Well, the bike has always been garaged and rarely ridden over winter but this year it’s been different. Because of another renovation project needing garage space the Skorpion has wintered outside under a waterproof cover. I know tank blistering is often blamed on fuel permeating through the plastic tank but it seems to me there must be something else going on to affect my bike now and not in the previous nineteen years. The blisters can be burst and there’s a small amount of fluid in them and it seems like water. Most of the blisters are above the level of the fuel in the tank but there is some below the fuel line. None of the other plastic parts painted in the same colour are affected.
The moral is don’t over winter your Skorpion under a waterproof cover.
It’s a bit of a sickener, that’s the polite version of what I’m really thinking.

Chicken pox tank

[lavrentyuk]

Mine too

[ralf]

Hello Richard, sorry to hear you have similar problems, do you have any similar circumstances ?

[Puffs]

Water ingress from outside? Suppose the tank is HDPE or so, a plastic to which paint sticks poorly.
Yes that would vex me...

[DAVID THOMPSON]

over here on the west side of the pond
we have a paint called krylon for plastic
i used it as a base coat on my traveller in hunter green and then used a green from a Chevy corvette
from the mid 1960's but the tank has not made it back on the bike its not a exact match but will do
dave

[Puffs]

In the UK Humbrol makes a primer called "Makes Paint Stick", especially for 'difficult surfaces including most plastics'. Note they say most; not sure how reliable it is on HDPE (high density polyethylene), particularly on the long term. I have 2 bikes with a HDPE tank, neither is painted.

Of course none of this helps you Ralf...
If it is caused by minute quantities of water permeating through the top coat, maybe keeping the tank in a dry & warmish atmosphere might reduce the blistering. Might take a while though. The little bond there was probably remains broken, so completely healing it that way seems unlikely.