i have a pro 42cccsa chain saw and when i try to start it,it kicks back at me as if the spark timing has sllpped (too far advanced)..how do i alter it.......

freddo, October 2010

You cannot change the ignition timeing, this is set by the flywheel/crank and key, it may have part sheared the key, you can increase the air gap between the flywheel and ignition unit, this will retard it slightly, you should also consider a de coke, it may be well carboned on top of the piston.

ADW, October 2010