Possible Fuel Breather Fault

[Mad Mark]

I have had a quick scan on here and found a few threads but thought I'd start another!

Yesterday I went to fill up and noticed my fuel cap had risen up a good 10mm or so. I am guessing that it must just be the heat had increased the pressure in the tank forcing the cap to lose its grip on the rubber connecting pipe between cap and tank. But surely the breather system should prevent this amount of pressure building up in the tank?

But then today Whilst driving it, I could smell large amounts of fuel fumes and not convinced they were from the boot which would be the most likely place if the cap had come lose.
I do sometimes get the 'woosh' of air as I open the cap and also hear the tank 'pop' as the pressure causes it to bulge in or out, but then this is nothing new I get that always in this heat!!

Would this mean the carbon breather can has become blocked? If so can this be cleaned out?

[Gray_101]

Theres an electric solenoid in the carbon canister, under the N/S rear wheel arch behind the fuel filter,,,,, i bet its stuck shut..

Id check that before any thing else

[Mad Mark]

How easy is this to check? I did read something on one of the other threads on here about blowing down a pipe or something!!

[ridds]

For the cap to rise that's a fair amount of pressure! From memory the filler neck is Sikaflexed to the body and then 2 jubilee clips retain the rubber joining pipe.

I'd check these for tightness as it shouldn't have been able to move the filler neck it they were tight.

[dean_ratpac]

i get a woosh... and i've had my carbon canister detached, and new breather pipes, but yesterday mine was under some serious pressure. I'm not if it was negative or positive pressure though...

[Mad Mark]

Ridds you are correct that is how it is fitted to the car and reconnecting this rubber pipe and re sealing the cap is the main job.
I am just hoping that the sealer has just got soft in the heat and also one of those clips has become loose allowing it to raise up!

But while I am at it want to make sure there are no more demons at work causing excess any pressure.

I have in this heat, like I said before, always had the woosh but never sure if its positive or negative either.
My biggest concern was the amount of fumes I could smell while driving.. when I did check in the boot the boot smelt ok which if it was the connecting pipe i would have thought the boot would have stank!!

[Mr Completely]

[jamaicanaccent]

You gotta be puttin' wonna deese up each a Ya nostrils maan, den one way or anudda, no problem !

[/jamaicanaccent]



Hope that helps, Sir

[Mad Mark]

hahaha!!! you crazy man!! I'd blow the car up with the amount of fumes I was getting!!

I re-fitted the filler cap, but not sealed it down yet, just tightened the jubilee clips and it seems ok! I gently blew through the breather pipe and it didn't seem blocked so hopefully was just a heat thing.