filler cap/fuel tank question

[RobD]

Hi
went to fill the brute up with diesel this morning,on opening the filler cap was greeted with a loud hiss,obviously a build up of gas escaping.Is this normal,if not how do I stop it from happening(don't want my fuel tank exploding!)

Cheers,Rob

[SparX]

Nothing to worry about , Just the fuel tank turns into a bit of a vacuum when the fuel is being sucked out of it by the fuel pump, so when you release the filler cap , it sucks in some air ( I think , but prepared to be shot down in flames )

My Old Honda CRX used to do this a hell of a lot , in fact I think it had an escape valve that used to croak / squeek through the night , took me ages to work out it was my car !

[Koi]

Nothing to worry about , Just the fuel tank turns into a bit of a vacuum when the fuel is being sucked out of it by the fuel pump, so when you release the filler cap , it sucks in some air ( I think , but prepared to be shot down in flames )

My Old Honda CRX used to do this a hell of a lot , in fact I think it had an escape valve that used to croak / squeek through the night , took me ages to work out it was my car !

Yep get the same, you will (well i do) notice it more the lower you get on diesel, say fill it right up and run it down to the white line more vacuum is created.

[RobD]

Yep get the same, you will (well i do) notice it more the lower you get on diesel, say fill it right up and run it down to the white line more vacuum is created.

Phew,no imminent explosions then,cheers.

[Guest]

There should be a vent on the tank somewhere (possibly on the cap) which should stop this happening. Only problem that it can cause is that if the blockage is bad you can get fuel starvation problems when there is still fuel in the tank because the pump can't draw against the vacuum.

Cheers

[da SLUG man]

i always thought it was because the tank on an injected motor was pressurised?!

my old rover used to make that noise too! (honda engine) it sounded like a cow mooing!

[TonyN]

A fuel injected motor will do this, never noticed it on a diesel before.

Check for a breather in the cap, but if its running OK, its probebly alright. Had a carbed car that the breather was blocked up, would run for 1/2 hour or so, then die. Took ages to work out what was going on!

[Gamedawn]

Mine gives a small hiss when I stop to fill up after a run - if it does it all the time probably worth checking the breather. My dad had a Granada that had the wrong fuel cap fitted (no breather) and it collapsed the fuel tank!

[SparX]

i always thought it was because the tank on an injected motor was pressurised?!

my old rover used to make that noise too! (honda engine) it sounded like a cow mooing!

Thats the sound down to a tee....

Kept me awake for hours at night trying to figure it out. !

Must be synonymous with Honda's !

[Guest]

A fuel injected motor will do this, never noticed it on a diesel before.

Check for a breather in the cap, but if its running OK, its probebly alright. Had a carbed car that the breather was blocked up, would run for 1/2 hour or so, then die. Took ages to work out what was going on!

Just filled mine up from empty and there was no hiss when I took off the cap - and yes there is a breather in the cap - so if yours hisses when you take off the cap then the breather is blocked - get a new cap.

Cheers

[RobD]

Just filled mine up from empty and there was no hiss when I took off the cap - and yes there is a breather in the cap - so if yours hisses when you take off the cap then the breather is blocked - get a new cap.

Cheers

WANTED:new filler cap for a 3rd gen(96)

[gemini]

Just filled mine up from empty and there was no hiss when I took off the cap - and yes there is a breather in the cap - so if yours hisses when you take off the cap then the breather is blocked - get a new cap.

Cheers

theres also usually a breather pipe from the tank as well, worth checking

[Robster]

Mine takes a deep breath when I take the cap off when the fuel getting pretty low...don't think there's a breather in the cap though.

Hasn't worried me so far mind you... seems to be behaving so no worries!

Rob

[slydog]

same here

yep mine hisses as well 96 3 ltr ssrx must all be same m8

[RobD]

yep mine hisses as well 96 3 ltr ssrx must all be same m8

Cheers,cancel that order.