Testing The Ignition; Using The Zat 4 Ignition Tester; Using The Zat 3 Ignition Tester - Stihl MS 460 Service Manual

7.1.3

Testing the Ignition

Module
To test the ignition module, use
either the ZAT 4 ignition system
tester 5910 850 4503 or the ZAT 3
ignition system tester
5910 850 4520.
The ignition test refers only to a
spark test, not to ignition timing.
1 2

Using the ZAT 4 ignition tester

5910 850 4503
– Before starting the test, install a
new spark plug in the cylinder
and tighten it down firmly,
b 3.5
: Remove spark plug boot and
connect it to the input
terminal (1). Push the tester's
output terminal (3) onto the spark
plug.
– Crank the engine quickly with the
rewind starter (min. 1,000 rpm)
and check spark in the tester's
window (2).
Warning!
The engine may start and
accelerate during the test.
MS 460, MS 460 C
If a spark is visible, the ignition
system is in order. If no spark is
visible in the window (2), check the
ignition system with the aid of the
troubleshooting chart, b 7.6
1
3

Using the ZAT 3 ignition tester

5910 850 4520
It is necessary to use the ZAT 3
ignition tester 5910 850 4520 to test
the booster gap.
– Before starting the test, install a
new spark plug in the cylinder
and tighten it down firmly, b 3.5
: Remove spark plug boot and
connect it to terminal (2).
: Attach ground terminal (1) to the
spark plug.
: Use adjusting knob (3) to set
spark gap to about 2 mm.
While using the ZAT 3, hold it only
by the handle (4) or position it in a
safe place. Keep fingers or other
parts of your body at least 1 cm
away from the spark window (3),
high voltage connection (2), ground
connection (5) and the ground
terminal (1).
3
Warning!
High voltage – risk of electrocution.
ZAT 3
– Crank the engine quickly with the
5910 850 4520
Warning!
2
The engine may start and
accelerate during the test.
If a spark is visible, the ignition
system is in order.
If no spark is visible in the
window (3), check the ignition
system with the aid of the
troubleshooting chart, b 7.6
rewind starter (min. 1,000 rpm)
and check sparkover in the
tester's window (3).
47