1996 Suzuki DT30C won't start when warm

[R11RT rider]

Recently serviced DT30C, carbs cleaned and rebuilt with new parts, runs great with a lot of high speed power and smooth low speed trolling operation. Starts on the second pull when cold. After running awhile and shutting it down, as when fishing for between 15 minutes to an hour, it does not want to start. I have tried placing the throttle in various positions, choking and not choking, and pulled until the rubber cord grip starts to blister my hand and it would not start. After being towed to the boat launch two times I started carrying aerosol Starting Fluid. Now by spraying into the airbox and waiting about 20 seconds the motor will start on the first pull. It would be nice if the motor would start when warm without the assitance of the starting fluid and would like to know if anyone has run into this problem before, or has any incite into it. All help is appreciated.

[boats.net]

Sounds like could be a possible vapor lock problem. When the problem is occuring try to force fuel to the carburetors with the primer bulb. If this does not correct issue verify carburetors are properly adjusted. Would not hurt to do a hot compression test and check for spark when unit is acting up.