fuel pissing outta filler neck on hard conering

[Fattony]

Just noticed the other day whilst doing some spirited driving in the old KE30 that it decideds to let some fuel out the filler neck (between the cap and filler neck). Ok, easy fix you say, its the rubber, so i put another rubber in there, 2 rubbers now and is real tight but it still leaks. Does anyone have an idea as to how to solve this problem ect. Only thing i can think of is that perhaps it requires a new rubber, might need to be soft for it to seal.

[thechuckster]

you may have the wrong cap? it should only allow liquid to escape if excess pressure builds up in the tank

[oldcorollas]

this is actualy relatively common on older corollas..

i suggest you go and buy a non-emissions cap (ie simple type, none of the shit on the back), but i cna' tremember which one it is... i think perhaps a chrysler part???

anyway, they leak through the emissions stuff apparently, so if you get one with no emissions bits (or a new emissions on eperhaps) it will be fine.

[Fattony]

i had considered the fact that the cap might have been building up pressure, but when opening the cap it doenst make the usual hissing sound, so its not sealing at all. But interesting that you suggest that it would be leaking through the emissions rubbish on the cap oldcorollas i might have to have a closer inspection of the cap and see where it might be getting through and then take to it with a welder if thats the case, but it looks to me that its getting through 2 seals ive put on there, which i found astounding as its extremely difficult to put on and release the cap.

[oldcorollas]

sound sweird i know.. but i had emissions cap on the KE1X (ke30 cap?) and on right handers it would piss fuel out.. the rubber was perfect, so i don't know exactly where ti was coming from....
changing to old style cap worked..... not sure about effect on the emissions equipment.

[bnicho]

This is a common problem on Minis too. It's often caused by poor sealing of the cap to the tank neck due to damage from levering off locking caps.

Beware that replacing a vented cap with a non-vented cap can cause problems!

If your car was designed to have a vented cap (some cars up to mid 70's) and you fit a non-vented one then the pump will create a vacuum in the tank and the eventually car will stop until you remove the cap. I did this once by accident to my Mini van and the suction of the facet pump actually dented the tank before the car stopped!

Check to see if your car has a seperate tank vent via a hose to the engine bay or simply dumping through the boot floor. If it has neither, then you need a vented cap.

Cheers,

[Fattony]

It has a charcoal can in the engine bay, which takes care of venting, so technically the cap should seal. I do believe that epa laws state that it was cars previous to 76 that didnt have to worry about a charcoal canister and hence were vented by tank cap to atmosphere.

[bnicho]

It has a charcoal can in the engine bay, which takes care of venting, so technically the cap should seal. I do believe that epa laws state that it was cars previous to 76 that didnt have to worry about a charcoal canister and hence were vented by tank cap to atmosphere.

Yes, that is correct.

In which case, you can (and should) use a non-vented cap.

Cheers,

[TA22 GT]

Fattony,
My guess is that either the main cap seal is leaking or the internal o-ring on teh end of the key barrell needs to be replaced.

If it leaks from the small holes near the centre of the cap then its most likely the internal o-ring. I had this issue with my TA22 GT.

Cheers,
Simon

[Fattony]

Thanks for the replies guys, and TA22 GT, i got a extra thick sealing on the outer seal, so i came to the conclusion the otherday its the inner o-ring seal, i had changed that with another second hand one at the time to, but still no luck, would anyone know of a sealer i can use that wont react with fuel?

[TA22 GT]

I'm guessing but I think a nitrile o-ring will be good for fuel. Check on the net or ask a local o-ring supplier which material to use.

cheers,
Simon

[Fattony]

Ive had it apart, is not a normal o-ring, its a funny arse pear shaped ring HRMMMM

[oldcorollas]

did it used to be a normal shaped one? ie, could a normal one fit in there?
nitrile can get hard and deform with time...

[Fattony]

Nope, the part of the filler that it sits in is that shape also

[TA22 GT]

Yep, that odd shaped o-ring is the one I was referring to as well as the one on the end of the barrel which is under the odd shaped ring.

Go to a wreckers and see if you can find one in better condition. From memory this type of o-ring is oalso on corollas etc, so see what you can find.

Cheers,
Simon