Check compression with a comp meter - should be 120psi or greater - 150 is about right for a new ring/piston, 170 for a new well running saw. If you can't do this, pick up the saw with the starter cord and it should fall slowly. Other than this, make sure the sparkplug is getting wet - you can heat up the plug with a blow lamp to make starting easier.
One thought - did you make sure the ring was located on the piston location dowel correctly - if not you may have big problems.You mak hav eoiled the cylinder to make the insertion of the piston easier and this oil may be fouling the plug - try warming it.
Steve, March 2009
