I have a 2000 150 hp ocean pro johnson that doesn't like to run after i shut it down. time could be five minutes or hours. i have to advance the throttle in neutral or gear to keep it lit. after i advance the throttle a few minutes it will settle down and idle. it isn't losing prime. the dealer tech did mess with the vapor seperator once. i was told the float was stuck and out of adjustment. the fuel pump was replaced also. other than that, cold start and operation is sharp and flawless. economy is excelent. any help?