Husqvarna ZTH, Operator'S Manual

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English-
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MAINTENANCE
Ignition System
The engine is equipped with an electronic ignition system. Only the spark plugs require maintenance.
For recommended spark plugs, see Technical Data.
1. Remove the ignition cable shoe and
clean around the spark plug.
2. Remove the spark plug with a 13/16"
(21 mm) spark plug socket wrench.
3. Check the spark plug. Replace the spark
plug if the electrodes are burned or if the
insulation is cracked or damaged. Clean
the spark plug with a steel brush if it is to
be reused.
4. Measure the electrode gap with a gapping tool. The gap shall be 0.75 mm. Adjust as necessary by
bending the side electrode.
5. Reinsert the spark plug, turning by hand to avoid damaging the threads.
6. After the spark plug is seated, tighten it using a spark plug wrench so that the washer is compressed.
A used spark plug should be turned 1/8–1/4 of a turn from the seated position. A new spark plug
should be turned 1/2 a turn from the seated position.
7. Replace the ignition cable shoe.
Checking the Safety System
The machine is equipped with a safety
system that prevents starting or driving under
the following conditions.
The engine can only be started when:
1. The mower deck is disengaged.
2. The steering controls are in the outer,
locked neutral position.
3. The driver is sitting in the driver’s seat.
4. The parking brake is on.
Make daily inspections to ensure that the
safety system works by attempting to start the
engine when one of the conditions is not met.
Change the conditions and try again.
If the machine starts when one of these
conditions is not met, turn the machine off
and repair the safety system before using the
machine again.
Check that the engine stops if one, after
having released the parking brake,
temporarily stands from the driver’s seat
(whether the mower deck is engaged or not).
Check that the engine stops if the mower deck is engaged and one temporarily stands up.
IMPORTANT INFORMATION
Fitting the wrong spark plug type can
damage the engine.
Inadequately tightened spark plugs can
cause overheating and damage the
engine. Tightening the spark plugs too
hard can damage the threads in the
cylinder head.
8011-527
Conditions for starting
IMPORTANT INFORMATION
In order to be able to drive, the driver
must sit in the seat and release the
parking brake before the steering
controls can be moved into the neutral
position, otherwise the engine will stop.