My boat won’t run at idle. Help!

[CaptainBString]

I have a Bayliner open bow 18’ with a Mercruiser 3.0 TKS SM WPS I/O engine. While getting ready for the summer I ran the engine (after pulling the plugs and giving it a fogging spray treatment). It seemed to run fine and yes I used ears to provide water to the engine while running. At one point the engine just conked out. I thought maybe it ran out of gas. After filling up with new gas the engine would start but only run on a high rpm before concking out. I could not get the engine to run at idle. There are new plugs and wires which were replaced last season. My boat has always run flawlessly. Does anyone have ideas on the problem and possible solutions?!? Thanks.

 

[alldodge]

could not get the engine to run at idle

Think the carb needs cleaning,
Take the fuel filter off and pour contents into a clear container (baggie, jar). See if there is anything but clean gas

 

[wellcraft-classic210]

debris in the float bowl blocking the inlets to the idle passage for fuel in your carb is 1 possibility // at higher rpm's the fuel is pulled through another passage.