This is just a general question, and really not related to an OMC motor. Truthfully, it relates to a 1972 JLO 400 Snowmobile motor. It was running great, then started running on one cyl. The one cyl has a yellow spark, and is not firing when the motor is running (I can pull the plug wire off, and it makes no difference). I was just wondering what parts I should be looking at replacing first.
With all of the older OMC's I've redone, coils, points, condensors, wires and plugs are just automaticly replaced. Parts for the JLO are harder to find, so I am just trying to do the repair in some sort of logical order.