50 hp force poor start /stalling

My 89 50 force seems to start right up when first started. Runs great but when i idle it down to an idle it will some times stall and not start after about 30 minnets of running. I took the carb apart cleaned it ( not much of anything in the way of dirt). At first i thought the plugs had fouled out so i changed them and the engine started and go me back to shore. I put new plugs in and went out again and it happened again. The only thing that i had done was raise and lower the engine the first time to change the plugs which lead me to think possible crap in the carb.

Has anyone had any thing to do with the fuel recovery system on these engines as i was reading in my manual this system ca cause problems like this.

Going out to try to fix as i have not played with anything this time.