Stihl MS 440 Service Manual

51MS 440, MS 440 C
7.6 Ignition System Troubleshooting
Engine does not run
Master Control lever
or separate stop switch
in position “#“?
Check the spark plug:
– Smeared with oil, black?
– Sooted?
– Electrode gap correct?
– Contacts shorted?
Clean the plug, reset
or replace
Check 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
Test ignition system with
ZAT3 or ZAT4
(use ZAT 3 as main spark gap
– see TI 32.94)
1

Stihl MS 440 Specifications

General

Displacement	70.7 cc
Chain Pitch	3/8"
Ignition system	Electronic
Starter	Recoil starter
Vibration reduction	Anti-vibration system
Weight (without bar and chain)	6.4 kg
Fuel tank volume	0.73 L
Oil Capacity	0.36 L
Guide Bar Length	40-63 cm
Guide Bar Length (recommended)	40-71 cm (16-28 in)