Home › Forum › Ask A Member › 1966 Evinrude 18hp… cough sputter cough! › Re: 1966 Evinrude 18hp… cough sputter cough!
Did you clean or replace the points, condensers and spark plugs? If points are cleaned, they also have to be polished to a mirror finish and cleaned with lacquer thinner or acetone to degrease them so they operate properly. Sometimes it easier and quicker to install new ones.
Bad plugs will cause a miss when the motor is being accelerated. So will bad points and capacitors. Backfiring is usually caused by a lean running condition which can be caused by a wrong carb adjustment or air leaking into the motor thru worn carb throttle shaft bushings or a worn top seal on the crankshaft. New packing washers on the needle will help to hold it in place and prevent any air leaks. TOP on the points cam identifies the top side of the cam itself for installation purposes. The points are at their widest opening for adjustment in this general area. I just do a visual for their widest opening before setting them at 0.020" if I don’t have a proper timing tool for setting them. Hope this helps some.