(T) Cinquecento (20/04/1994) leaking fuel

Hello. Our car has very recently started dripping fuel when the tank is roughly over 3/4 full. The tank itself does not appear to be leaking but someone has told me that because the height of the top of the fuel tank is not far below the height of where the petrol cap is, that there is some sort of mechanism that should stop fuel flowing back through the overspill pipe and that this mechanism may have failed. I'm afraid I'm not at all technical but I've done my best to explain the problem !!!. Can anyone with knowledge of Cinquecentos of this period help please ???.

Short of using

'tenacento'

The pipes that run up to the filter pass through the inner sill just behind the drivers door, is that where your leak is?

Cheers

PD

Hello Rallycinq and many thanks for your reply. Yes, the leak does appear to be coming from around that area. Sorry I'm not at all mechanically minded, when you refer to the filter do you mean the fuel filter ???.
Cheers,
Mark

Sorry, typo.

It should read

Filler

Cheers

PD