Removing The Spark Plugs; Checking The Spark Plugs - Toro 73547 Wheel Horse 520Lxi Operator's Manual

Maintenance

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.
1
Figure 33
1. Spark plug wire
32
2
m–3428
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
1
Figure 34
1. Center electrode insulator
2. Side electrode
Installing the Spark Plug
1. Install the spark plug(s) and metal washer. Make
sure the air gap is set correctly.
2. Tighten the spark plug(s) to 15–20 ft-lb
(20–27 Nm).
3
m–3215
3. Air gap (not to scale)
(s)