help su carb problem

[bagof]

my piggy failed to procede yesterday and now i swear its trying to send me to the nut house (again) the problem is :engine lost power then died. after a few mins it fired and ran for 2mins fine then died again. it felt like lack of fuel and fuel filter looked dry ,after removing filter it ran fine for 10miles then died 200yards from home after checking spark (fine on all plugs) fuel pump(good flow).ifitted new su carb still dead. checked a plug: bone dry! but fuel is getting to carb as bowl is full what is going on!! any ideas cheers rob

[garagewidow]

check the float chamber has no debris in the bottom,even though it's a new carb some could have come from the fuel pipe and it finds it's way into the jet tube and blocks it.another common problem is when refitting the fuel pipe sometimes the brass pipe can shear off a piece of the rubber hose which acts like a flapvalve and again can block or severly restrict flow to the carb.as you have flow from the pump i am assuming you have sufficient pressure(1.5-2psi is all),another possibility is an air leak between carb and head,less likely though.