Re: 3 hp mercury
yes, it should be fine idling. I recommend if thats all your doing with the motor, lean it out a bit on the mixture (assuming its a premix obviously) maybe 75:1 with a good quality TCW-3 rated oil. Do not run WOT however as this may be too lean, but for idling, it should be fine at will idle a lot better. 2 strokes do not like to sit and idle all day long on a rich mixture.
