Toro 74433 Operator's Manual page 30

Figure 38
1. Spark plug wire
4. Remove the spark plug and metal washer.
Checking the Spark Plug
1. Look at the center of the spark plug (Figure 39).
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. Always
replace the spark plug when it has a black
coating, worn electrodes, an oily film, or cracks.
2. Check the gap between the center and side electrodes
(Figure 39). Bend the side electrode (Figure 39) if
the gap is not correct.
Figure 39
1. Center electrode insulator
2. Side electrode
Installing the Spark Plug
1. Install the spark plug. Make sure that the air gap is
set correctly.
2. Tighten the spark plug to 30 ft-lb (41 N-m).
3. Push the wire onto the spark plug (Figure 38).
4. Close the access panel and tighten the fasteners to
secure it shut.
2. Muffler
3. Air gap (not to scale)
Important: Always make sure the panel
is replaced and secured with the fasteners
before operating the machine. Operating the
machine with the access panel open would allow
clippings and other debris entering the engine
compartment possibly damaging the machine.
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