Toro 73547 Wheel Horse 520Lxi, Operator'S Manual

Page: 37 / 60

Maintenance
35
Removing the Spark Plugs
1. Disengage the power take off (PTO), set the
parking brake, lower the attachment lift, and turn
the ignition key to “STOP” to stop the engine.
Remove the ignition key.
2. Open the hood.
3. Pull the wire(s) off the spark plug(s) (Fig. 33).
Now clean around the spark plug(s) to prevent
dirt from falling into the engine and potentially
causing damage.
4. Remove the spark plug(s) and metal washer.
2
1
m–3428
Figure 33
1. Spark plug wire 2. Spark plug
Checking the Spark Plugs
1. Look at the center of the spark plug(s) (Fig. 34).
If you see light brown or gray on the insulator,
the engine is operating properly. A black coating
on the insulator usually means the air cleaner is
dirty.
IMPORTANT: Never clean the spark plug(s).
Always replace the spark plug(s) when it has:
a black coating, worn electrodes, an oily film,
or cracks.
2. Check the gap between the center and side
electrodes (Fig. 34). Bend the side electrode
(Fig. 34) if the gap is not correct.
2
3
1
m–3215
Figure 34
1. Center electrode insulator
2. Side electrode
3. Air gap (not to scale)
Installing the Spark Plug
(s)
1. Install the spark plug(s) and metal washer. Make
sure the air gap is set correctly.
2. Tighten the spark plug(s) to 17 ft-lb (23 Nm).