Stihl MS 650 Manual page 14

Condition
No spark
MS 650, MS 660
Cause
Faulty insulation or break in ignition
lead or short circuit wire.
Check operation of spark plug.
Inspect Master Control lever,
ignition coil/lead for damaged
insulation and leakage current
Remedy
Use ohmmeter to check ignition
lead for break. If break is detected
or high resistance measured, fit a
new ignition lead; check short
circuit wire for ground contact in run
position
Clean or replace spark plug,
replace faulty parts of ignition
system
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