9Series 4180 Powerhead
4.3 Ignition System
Warning:
Exercise extreme caution while 
carrying out maintenance and repair 
work on the ignition system. The
ignition system. The high voltages 
which occur can cause serious or 
fatal accidents.
Condition Cause Remedy
Engine does not run No spark Check operation of slide control 
and ignition module; replace 
damaged parts
Spark plug dirty or faulty Clean or replace spark plug
Faulty insulation or break in ignition 
coil, ignition lead or short circuit 
wire 
Use ohmmeter to check ignition coil 
and lead for break. If break is 
detected or resistance is high, fit a 
new ignition coil and ignition lead; 
check short circuit wire for ground 
contact in run position
Engine runs roughly, misfires, 
temporary loss of power
Spark plug boot is loose Press boot firmly onto spark plug 
and fit new spring if necessary
Spark plug sooted, smeared 
with oil
Install new spark plug
Weak spark or no spark Faulty insulation on ignition lead or 
short circuit wire. Use ohmmeter to 
check ignition lead for break. If 
break is detected or resistance is 
high, fit a new ignition lead. 
Wrong air gap between ignition coil 
and flywheel 
Reset air gap
Flywheel cracked or damaged Install new flywheel
Spark plug dirty or faulty. Check 
slide control, ignition coil/lead for 
damaged insulation and leakage 
current.
Clean or replace spark plug. 
Replace damaged parts of ignition 
system