Fisherman wrote:
I spent several hours researching this and was convinced the problem was caused by a broken belt or slipped timing chain also, especially because nether cylinders had compression. I finally found a service manual and found that there is no belt or chain that controls timing but timing is controlled with an ignition module(coil) and there are no adjustments or points. Having said that I also noticed that there is a gap between the ignition module and the magneto. I replaced this module several years ago and set this gap to about .030 or so. I really don't understand how this controls the timing, but if the set screws loosened through vibration and the gap was smaller or larger would this change the timing? Would this have the same effect as a broken belt or timing chain slipping a couple of teeth?
Timing chain or belt controls the opening/closing of the valves unless it's a pushrod model. Ignition timing has nothing to do with the compression
My understanding is if the valve timing jumps, you'll get little or no compression equally in all cylinders, because valves fail to open and close at the right time. What am I missing?
