ORIGINAL: pattratt
Keith
This is a new engine and all new fuel tubing but good idea to replace all to be sure this is not the problem.
I have already checked the valve cover gasket for tightness and this engine does not use an external check valve. I will check the plug and head bolts.
Dick,
Even though your valve cover may be tight there may be a slight high spot on the surface thus allowing air/fuel to escape. Take the valve cover off and remove the gasket and sand it on some 600-800 sandpaper until you get it shiny all over - then clean it in alcohol and put it back with a new gasket.