Hissing from the fuel tank

[matts_FTO]

Over the past few months i've noticed a variety of hissing sounds coming from the fuel tank!

Its quite a detectable sound even with engine ticking over. When i first heard it i thought it was coolant dripping on the exhaust somewhere, but then i realised it was coming from the rear. I opened the fuel cap and then it became obvious it was in the tank.

Originally i thought it'll be air in the fuel line/pump somewhere but it's still ongoing!

Any ideas?

Thanks, Matt

[Sgt_Major]

mine only hisses when I open it and its low....

maybe just a leak round the seal?

[matts_FTO]

Thanks for the reply (its the first i've had out of all the threads i've put on, i was starting too think i'd done something wrong!)

I've guessing you mean the seal on the inside of the filler cap? If so then it cant be this as it still makes the noise with the cap off as i did this and put my ear to the filler neck.

I havnt had the tank past 1/4 full since march as its been off the road while i've been working on it - maybe filling it might help push out any air gaps in the fuel line?

[Sgt_Major]

Could be.... it's a strange one for sure.

Maybe a tiny hole in the fuel line?

[matts_FTO]

Once again thanks for the reply.

Yes that could also be a possibility. I cant smell any fuel vapour though, but still a possibilty.

If i ever get to the bottom of it i'll let everyone know!