I've got a 1985 Merc. 150 Black Max that recently started running very rough between 1200 and 2000 rpm. Can't have this as my offshore trolling speed is obtained in that range. I know these motors arent the smoothest, but it much worse that before. Fuel system is in tip top shape. New lines, rebuilt pump and carbs, new filters, etc. Seems like a plug(s) is fouling or not firing. Is is safe to remove the plug wire while running in this range in an attempt to find a dead cyliner by drop or no change in rpm. If not, is there another method I should use. She runs great at idle and above 2000. No coughing, sputtering or smoking. Just loads of power.<br /><br />Any other things I should look at? Most wiring under the cowl seems very pliable. Is this normal?<br /><br />Thanks.<br /><br />Brian