sounds like a clogged pilot jet or air screw needs adjusted
get it to idle, however, try the choke knob first
then adjust the air screw 1/2 turn at a time, allowing 20-30 seconds between turns to allow the engine to adjust to the new setting, till you find where it idles the highest, that should be between 1/2 and 2-1/2 turns out
if under 1/2 turn= leaner pilot
over 2-1/2 turns = richer pilot
get it to idle, however, try the choke knob first
then adjust the air screw 1/2 turn at a time, allowing 20-30 seconds between turns to allow the engine to adjust to the new setting, till you find where it idles the highest, that should be between 1/2 and 2-1/2 turns out
if under 1/2 turn= leaner pilot
over 2-1/2 turns = richer pilot