Sometimes I noticed an intermittend sound coming from the fuel pump. So I decided to check the fuel check valve. When I removed the cover underneath the fuel tank, the hose connecting the pump and the tank started dripping fuel immediately. There was no fuel smell before.
Turns out BOTH clamping rings that hold the hose connecting pump and fuel filter were rusted and broken into pieces. Quite unbelievable it didn't leak.
Might be worth checking. You can access the hose quite easily by removing the smaller piece of the fuel tank cover. Only 2 little screws.
