I have a 1982 Chrysler Sea King 15hp. Just replaced head gasket and rebuilt the carb. When I'm running WOT, it surges down. Found out today that if I pump the fuel line bulb while running wot it runs just fine, stays and doesn't surge. Is this the fuel pump? Also have noticed air bubbles in my internal fuel lines but no fuel leakage so assuming it's not an internal fuel line issue. Any help, ideas or questions would be appreciated! Thanks!!