Wen DF472X

To inspect or replace the spark plug:
1. Pull on the spark plug boot to remove it (Fig. 19). Be careful not to
tear insulation or wire.
2. Remove the spark plug rubber boot and unscrew the spark plug
from the engine using the spark plug wrench provided.
TIP: There is limited space for the wrench to turn. Use both rows of
holes in the spark plug wrench to gain leverage to loosen the plug.
3. Visually inspect the spark plug. If it is cracked or chipped, or if
the electrodes are worn or burned, discard it and replace with a new
spark plug.
We recommend replacing with an NGK BP7ES/Torch F7TC spark plug
(part no. DF475-145), available for purchase at
wenproducts.com.
4. If re-using the spark plug, use a wire brush to clean any dirt from
around the spark plug base, then re-gap the spark plug.
5. Measure the plug gap with a spark plug gap gauge. The gap should
be 0.7 to 0.8 mm (0.028-0.031 in.) (Fig. 20). Carefully adjust the gap
if necessary.
6. Screw the spark plug back into the spark plug hole using the spark
plug wrench. Do not over-tighten spark plug. Recommended tighten-
ing of spark plug is ½ to ¾ of a turn (15 ft-lb torque/20.33 Nm) after
spark plug gasket contacts spark plug hole.
7. Reinstall the spark plug boot over the spark plug.
SPARK PLUG MAINTENANCE
Refer to Recommended Maintenance Schedule for maintaining the spark plug.
The spark plug is important for proper engine operation. Check the spark plug regularly to maintain proper engine
operation. A good spark plug should be intact, free of deposits, and properly gapped.
MAINTENANCE
Fig. 19
Spark PlugSpark Plug
BootBoot
Spark Plug
Boot
Fig. 20
0.7 - 0.8 mm
CylinderCylinder
AssemblyAssembly
Cylinder
Assembly
29