Operator's Manual

Maintenance
11
Replacing the Spark Plug
Use an NGK BPMR4A spark plug or equivalent. The
correct air gap is 0.032” (0.8 mm). Remove the plug
after every 25 operating hours and check its
condition.
1. Stop the engine and pull the spark plug wire off
of the spark plug.
2. Clean around the spark plug and remove the plug
from the cylinder head.
IMPORTANT: Replace a cracked, fouled or
dirty spark plug. Do not sandblast, scrape or
clean the electrodes because engine damage
could result from grit entering the cylinder.
3. Set the air gap to 0.032” (0.8 mm) (Fig. 10).
4. Reinstall the correctly gapped spark plug and
gasket seal. Tighten the plug firmly to 10 ft-lb
(13.6 Nm).
986
.032”
(0.8 mm)
Figure 10
Cleaning the Cooling System
Cleaning the cooling system ensures correct cooling,
best engine performance and maximum engine life.
1. Clean any dirt and chaff from the cylinder,
cylinder head fins, and from around the
carburetor and linkage (Fig. 2).
2. Remove any debris from around the air intake
slots on the recoil housing (Fig. 2).
1
2
Figure 11
1. Air Slots in Recoil Housing 2. Cylinder Head FIns