Troubleshooting Chart - Stihl MS 440 Service Manual

13.1

Troubleshooting Chart

temperature = +20 °C (68 °F)
between +13 °C (55 °F) and
between +6 °C (43 °F) and
Carburetor heating system
80
Measure resistance of
heating element at
Resistance
approx. 8 Ohm?
yes
Check thermostatic
switch
Does the switch close
+6 °C (43 °F)?
yes
Does the switch open
+13 °C (55 °F)?
yes
in order
Replace heating
no
element
Replace thermostatic
no
switch
Replace thermostatic
no
switch
MS 440, MS 440 C