Spark Plug
Service Interval/Specification
Install a new spark plug after every 100 operating
hours. Make sure the air gap between the center and
side electrodes is correct before installing the spark
plug. Use a spark plug wrench for removing and
installing the spark plug and a gapping tool/feeler
gauge to check and adjust the air gap.
Type: Champion RC–12YC (or equivalent)
Air Gap: 0.030" (0.762 mm).
Removing the Spark Plug
1.
Disengage the blade control (PTO), set the
parking brake, and turn the ignition key to
"OFF" to stop the engine.
2.
Open the hood.
3.
Pull the wire off the spark plug (Fig. 20). Now
clean around the spark plug to prevent dirt from
falling into the engine and potentially causing
damage.
4.
Remove the spark plug and metal washer.
1
2
Figure 20
1. Spark plug wire
1798
2. Spark plug
Checking the Spark Plug
1.
Look at the center of the spark plug (Fig. 21). 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 (Fig. 21). Bend the side electrode
(Fig. 21) if the gap is not correct.
2
1
Figure 21
1. Center electrode insulator
2. Side electrode
Installing the Spark Plug
1.
Install the spark plug and metal washer. Make
sure the air gap is set correctly.
2.
Tighten the spark plug to 15 ft-lb (20.4 Nm).
3.
Push the wire onto the spark plug (Fig. 20).
4.
Close the hood.
Maintenance
3
0.030"
(0.762 mm)
1870
3. Air gap (not to scale)
21