need some help. i just broke in a new motor. using the heat cycle. and it sounds like a popcorn machine. sounds like its poppping all the time. but runs very strong and fast as h------l. i did seal the back plate. it's still running rich. . temps stay under 225.

what engine? fuel% glow plug and #
is it a pop from it while its running?
if so does it happen when you hit the throttle,it sound like a pre detonation

it's a picco 26 outlaw. using a 0s8 plug and 30% o'DONNELL

get a picco,idm or siro plug,
how does the plug look,is it pushed in?
you may have to go up one copper shim

the motor has 3 shims now? the plug is good nothing pushed in?