Short Circuit Wire / Switch; Testing; Removal And Installation - Stihl TS 420 Manual

: Ensure that the machined key
(arrow) engages in the groove on
the crankshaft stub.
– Check the air gap between
ignition module and flywheel,
adjust if necessary, b 8.1.1.
– Reassemble remaining parts in
reverse order.
– Tightening torques, b 3.5.
8.6

Short circuit wire / switch

8.6.1

Testing

Check the short circuit wire if the
spark plug and ignition lead with
spark plug boot are in order.
– Remove the fan cover, b 7.3.
: Disconnect the short circuit
wire (1).
56
– Connect the ohmmeter to
ground (arrow) and the short
circuit wire (1).
– Set the switch shaft to "
The resistance measured must be
about 0 ohm. If it is much higher, the
reason is a break in the wire and the
switch must be replaced, b 8.6.2.
– Set the switch shaft to "F".
The measured resistance must be
infinitely high, otherwise replace the
switch, b 8.6.2.
If no fault can be found, test the
ignition system in accordance with
flow chart, b 8.7.
– Test the complete switch unit for
continuity.
– Reassemble parts in reverse
order.
1
8.6.2

Removal and installation

The switch, short circuit wire and
ground wire form a single unit. The
0
".
complete switch must be replaced if
there is any sign of damage.
– Remove the shroud, b 7.4.
– Remove the fan cover, b 7.3.
: Remove the spark plug boot (1).
– Pull the ignition lead out of the
cable guides (arrows).
1
: Disconnect the ground wire (1)
and short circuit wire (2).
1
2
TS 410, TS 420