"The idle may need to be adjus
"The idle may need to be adjusted while in Forward gear. On my mercury, idle is adjusted to 500-600 RPMs while in Forward gear. Neutral has no resistance (prop is not spinning) and when the IDLE is set while in NEUTRAL, you may have problems. When gear is shifted into FORWARD gear, engine now has resistance and the RPMs will decrease around 200 RPMs and your "Ideal" idle settings have dropped from 500-600 to 400 and will stall the engine; set the idle while in Forward gear, not NEUTRAL gear. This will result in a higher IDLE noise and speed while in neutral, but your engine will no longer stall."