It will prime with the electric starteronly when i have my my finger over the carb.
You'll end up flooding the engine and breaking the conrod doing it thid way with the starter.
Hold throttle wide open, flip,flip, flip --three or more times while the fuel in the line hits the carb. Close the throttle, flip,flip, flip, open 1/4 throttle and hit it with the throttle.
Break it in the way the manual says. If not do a search on "break-in and ringed and engine" and you'll find loads of info. General concencis is to break them in rich:
http://www.rcuniverse.com/showthread...ged+and+engine
It'll be a good strong engine, just be patient..