Husqvarna K1270 II Workshop Manual page 27

The ignition system has a primary coil (1) and a
secondary coil (2). They are wound around an iron core
(3). An electronic digital unit (4) controls the switch
function.
The voltage sequence is in the diagram in the
illustration. The dotted line shows the voltage if the
current is not broken.
Current moves through the coil by the permanent
magnet on the flywheel. The electronic digital unit
senses the voltage in the primary coil. It breaks the
current before the piston is at the high turning point.
Until this point, the primary coil is in a closed circuit.
With an open circuit the current stops flowing and
voltage increases from 5V (Volt) to approximately 200V.
The primary and secondary coil work as a step-up
transformer. The secondary coil increases the voltage to
20 000V. This causes a spark.
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6.2.2 Ignition unit
The ignition unit is sealed and cannot be repaired. The
spark plug cable, the contact unit to the spark plug and
the seal on the ignition unit can be replaced.
1. Stop switch
2. OilGuard
6.2.3 To examine the ignition system
Examine the ignition system first if the engine does not
start.
6.2.4 To examine the ignition spark
1. Ground the spark plug to the cylinder.
2. Move the stop switch to the operation position.
3. Pull the starter rope handle.
If there is no spark, the problem can be a defective
spark plug, defective ignition cable or a damaged short
circuit cable. Examine the spark plug.
6.2.5 To examine the spark plug
The electrode gap must be .02 in/0.5 mm.
The electrodes must be free of dirt and oil. Clean with a
wire brush.
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Repair and servicing - 27