Help everyone. My motor will crank right up from the ramp. I can go 2 miles out in saltwater. Cut engine off and use trolling motor for a while. Then when ready to head another direction, boat motor will turn over when I turn the key but will not start. The only way it will start is if I pull warm up level all the way up and running for a few minutes, then push lever down in a hurry and throttle up quickly and then it will run fine, until I shut it off again. Last weekend I took to local lake and it did not happen once. This intermittent thing is so crazy. I have had spark plugs changed, oil change, gas lines and filters changed, fuel pump replaced, fuel water filter changed, carbuerators completely rebuilt, run non ethanol with ring free additive mixed in and still have problem. Recently empty fuel tank and put fresh non ethanol gas in tank. Anybody who has ever heard about a motor doing this or witnessed it with their own, that could give me any ideas, would be greatly appreciated.