Thank you for noticing. The pump is good, I tried to suck pump five liters of petrol into cans. It was done in a moment .. I'll try to find more air into the tank (but I tried it with the lid open). Strangely, the supply hose from the pump to flow out once ca 1dcl gasoline and then just a trickle ... wait a moment and again 1dcl ... it repeats ... Does anybody have a drawing inside of the fuel tank (not much in the manual)?