Leak coming from Fuel tank..

[Grenuj]

Hi there experts
I have filled my fuel tank up with 20liters.. I could smell it petrol vapour from a petrol cap (inside).
I have an overflow pipe in the filler neck. For me, function of overflow pipe is not necessarily completely obvious..what is it really for?
I have checked the main tank connections and they look ok dry to the touch.
See photo's for better detail..

 

[harbourseal]

It is a breather pipe. It lets the air out of the tank while you are filling the tank. And it lets air in while you are using fuel for driving. To prevent a vacuum and thus a shortage of fuel in the carburetor.

 

[edwin]

With our tank, we developed micro holes around the drain plug of the tank. The plug was good, but the low area around, where water would collect under the petrol, was rusting from the inside out. It smelled of petrol and just looked damp, with the darkening of the dirt . I got another tank, restored it with the coating to the inside and installed that, which has worked well. Stopped the smell , no leak. Edwin