Operator's Manual
Maintenance
25
Spark
Plug
Service Interval/Specification
Check the spark plug(s) after every 200 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(s) and a gapping tool/feeler
gauge to check and adjust the air gap.
Type: Champion RC-12YC (or equivalent)
Air Gap: 0.040” (1.02 mm)
Removing the Spark Plug(s)
1. Disengage the power take off (PTO), set the
parking brake, and turn the ignition key to
“OFF” to stop the engine. Remove the ignition
key.
2. Open the hood.
3. Pull the wire(s) off the spark plug(s) (Fig. 23).
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).
2
1
1218
Figure 23
1. Spark
plug wire
2.
Spark plug
Checking the Spark Plug
1. Look at the center of the spark plug(s) (Fig. 24).
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 r
eplace 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. 24). Bend the side electrode
(Fig. 24) if the gap is not correct.
0.040”
(1.02
mm)
2
3
1
Figure
24
1. Center
electrode insulator
2.
Side electrode
3.
Air gap (not to scale)
Installing the Spark Plug(s)
1. Install the spark plug(s). Make sure the air gap is
set correctly.
2. Tighten the spark plug(s) to 20 ft–lb (27 Nm).
3. Push the wire(s) onto the spark plug(s) (Fig. 23).
4. Close the hood.