I know this is a really old thread but i had this problem
i took the vacuum and fuel lines of and sucked on the vacuum hose to see if fuel would flow out of the fuel hose but non did, I then proceeded to remove the fuel tap from the tank and rinse the tank with some fuel
I then checked that both of the wire connections in the tap where ok as i thought that maybe if the circuit was broken it may prevent fuel from flowing, I then replaced the tap/filter and and sucked sucked again this time fuel flowed I also soldered the little end piece that connects to the carb into place and melted the plastic hose onto both end attachments to make sure the connections where air tight, and heyyy presto It worked 5-6 kick
< Me on the left
October 2012