Just bought a little 17 foot metal boat with a 50 HP Johnson (1999 model two stroke) The motor starts great and runs good above about 2000 to 2500 rpm but when I slow down it idles very rough and the motorshakes badly like its running on one cylinder. Any ideas?
Hi fountainboater.Congratulations with your purchase. The bad iddle can have several reasons. The first I would check, and that would be before I run it more, is that the motor is getting fuel from both carbs. Remove and throughly clean both carbs. Pay special attention to the small holes in top of carb body, above and behind throttle. Theese are your intermediate and iddle nozzles. They can be difficult to clean properly. Get carb cleaning liquid, remove all plastic parts from carbs and soak overnight in the liquid. Blow through with compressed air. Get a manual from library and do the syncÂ´n linck procedure. If problems, post again. Running in a lean condition caused by clocked up carbs can score cylinder and burn piston badly - dont.