Stihl MS 661 Manual page 58

7.13 Ignition System Troubleshooting
MS 661, MS 661 C-M
Engine does not run
Stop switch:
– in position "
Check the spark plug:
– Smeared with oil, black?
– Sooted?
– Electrode gap correct?
– Contacts shorted?
– Clean, readjust or replace the spark plug,
b 7.5
Check the spark plug boot:
– Firmly seated on plug (leg spring)?
– Leg spring hook in center of ignition lead?
– Boot damaged?
– If necessary, install new spark plug boot and/
or leg spring,
b 7.6
Test ignition system:
with ZAT 3 or ZAT 4
(use ZAT 3 as main spark gap
see TI 32.94),
b 7.5
1
F
"?
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