g027478
Figure 34
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).
g027479
Figure 35
Installing the Spark Plug
Tighten the spark plug to 25 to 29 N∙m (18 to 22 ft-lb).
g027938
Figure 36
Cleaning the Blower
Housing
To ensure proper cooling, make sure that the grass
screen, cooling fins, and other external surfaces of the
engine are kept clean at all times.
Annually, or every 100 hours of operation (more often
under extremely dusty, dirty conditions), remove the
blower housing and any other cooling shrouds. Clean
the cooling fins and external surfaces as necessary.
Make sure that the cooling shrouds are installed.
Torque the blower housing screws to 7.5 N·m (5.5
ft-lb).
Important:
Operating the engine with a blocked
grass screen, dirty or plugged cooling fins, and/or
cooling shrouds removed, causes engine damage
due to overheating.
32
