Servicing the Spark Plug
Service Interval:
Every 50 hours—Check the spark plug.
Every 100 hours—Replace the spark plug.
Ensure that 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 or feeler gauge to check and adjust the air gap.
Install a new spark plug if necessary.
Type:
Champion RC12YC, Autolite 3924, NGK BCPR6ES
or equivalent
Air Gap:
0.76 mm (0.03 inch)
Removing the Spark Plug
1.
Disengage the blade-control switch, move the motion
controls outward to the P
ARK
position, stop the engine,
and remove the key.
2.
Before removing the spark plug(s), clean the area
around the base of the plug to keep dirt and debris out
of the engine.
3.
Remove the spark plug (
).
B
A
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Figure 33
Checking the Spark Plug
Important:
Do not clean the spark plug(s). Always
replace the spark plug(s) when it has: a black coating,
worn electrodes, an oily film, or cracks.
Note:
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.
Set the gap to 0.76 mm (0.030 inch).
B
A
g027479
Figure 34
Installing the Spark Plug
Tighten the spark plug to 20 N-m (15 ft-lb).
B
A
15 ft-lb
20 N-m
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C
D
Figure 35
33
