Working on an Intek 11HP walk behind mower. Owner recently installed a new fuel pump, said the engine ran for a few seconds, then quit. Checked carb, clean inside, started mower and would only run at a slow RPM, and smoked. Pulled breather hose and fuel was leaking out. Checked needle and seat, also o-ring on the seat housing, all looked OK. Tried bypassing the fuel pump by elevating the fuel tank and gravity feeding the carb, still same problem. Could there be any other thing bad besides the needle and seat? Thanks, Roy H.