well i got round to "sealing" it with some selleys knead-it...sealled it alright...about a month ago when it was 40deg. i drove to ballarat...3/4 way there my car started making a horrible noise. hard to explain, but it scared the shit out of me. when i got to ballarat, i went to fill up. when i opened the cap there was so much pressure built up in there it fizzed and hissed for about a minute or two!!! it sounded like the fuel was boiling!!! the inlet flap was hot too, could hardly touch!! i got scared, thought it was gonna blow up, so i put the cap on after it calmed down a bit. 5 min later i took the cap off again, and it hissed and fizzed like before! i ended up driving around with the cap on half way so it leaked but didnt build up pressure.
that was the only time it has done that since, but it hasnt been that hot since then either. can an extra 5 - 10 deg. do that to a fuel tank...(maybe under pressure?) is it as dangerous as it sounded? or am i worried about nothing? how do i fix?