maintenance
Ignition System
The engine is equipped with an electronic ignition system. Only the spark plug requires maintenance.
1.For recommended spark plugs, see Technical Data.
2.Remove the ignition cable boot and clean around the spark plug.
3.Remove the spark plug with a spark plug socket wrench.
4.Check the spark plug. Replace the spark plug if fouled, the electrodes are burned and if the insulation is cracked or damaged. Clean the spark plug with a steel brush if it is to be reused.
5.Measure the electrode gap with a gapping tool. The gap should be .030" (0.75 mm). Adjust as necessary by bending the side electrode.
6.Reinsert the spark plug, turning by hand to avoid damaging the threads.
7.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 of a turn from the seated position. A new spark plug should be turned ¼ a turn from the seated position.
8.Replace the ignition cable.
Safety System
This 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.
Make sure the engine stops when the park brake is not engaged and the operator leaves the seated position.
Check that the engine stops if the mower blades are engaged and the driver temporarily moves off the driver's seat.
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.
Measure the electrode gap
Start conditions
IMPORTANT INFORMATION
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.
Husqvarna - 39
