Stihl MS 391

50 MS 311, MS 391
Machine runs trouble-free,
no further action necessary
no
Install new ignition
b 7.3
yes
no
– Look for fault in fuel system or
carburetor
– Check engine for leaks
– Check position of flywheel on
crankshaft,
b 7.6, b 6.5
yes
Check operation
of switch shaft:
– Short circuit wire chafed?
– Function between contact spring and switch
shaft contact:
– Position "F" = no connection
– Position "
0" = connection
– Install new short circuit wire if necessary,
b 7.7.2
2
3
Powerful
spark?
Engine
runs?