Stihl MS 311 Manual

39MS 311, MS 391
7. Ignition System
Exercise extreme caution when
troubleshooting and carrying out
maintenance or repair work on the
ignition system. The high voltages
which occur can cause serious or
fatal accidents.
Troubleshooting on the ignition
system should always begin at the
spark plug, b 2.3
– Remove the fan housing, b 8.2
The electronic (breakerless) ignition
system basically consists of an
ignition module (1) and flywheel (2).
7.1 Ignition Timing
Ignition timing is fixed and cannot
be adjusted during repair work.
Since there is no mechanical wear
in these systems, ignition timing
cannot get out of adjustment during
operation.
2
1
4903RA253 TG
7.2 Preseparator
– Remove the fan housing, b 8.2
: Take out the screw (1).
: Remove the preseparator (2).
– Reassemble in the reverse
sequence.
7.3 Ignition Module
The ignition module accommodates
all the components required to
control ignition timing. There are
two electrical connections on the
coil body:
– High voltage output (1) with
ignition lead
– The connector tag (2) for the
short circuit wire
2
1
4903RA254 TG4903RA092 TG
2
1
Testing in the workshop is limited to
a spark test. A new ignition module
must be installed if no ignition spark
is obtained (after checking that
wiring and stop switch are in good
condition).
Removing
– Remove the shroud and pull off
the spark plug boot, b 6.4
– Remove the fan housing, b 8.2
– Remove the preseparator, b 7.2
: Pull the ignition lead (1) out of the
cable channel (arrows).
: Disconnect the short circuit
wire (1).
: Take out the screws (2).
: Remove the ground wire (3).
– Remove the ignition module.
4903RA215 TG
1
1
3
4903RA255 TG
2
2

Stihl MS 311 Specifications

General

Oil tank capacity	0.348 L
Fuel tank capacity	0.6 L
Power source	Gasoline

Weight and Dimensions

Weight	6200 g