Figure 4-3. Check Spark Plug Gap
Finger tighten spark plug, and then using a spark
7.
plug socket, tighten to 15 ft-lbs (20 N-m).
Install spark plug cable onto spark plug.
8.
4.7 — Check/Adjust Valve Clearance
IMPORTANT: If uncomfortable performing this proce-
dure or the proper tools are not available, take the
generator to the nearest service center to have the
valve clearance adjusted. This procedure is a very
important step to ensure maximum engine service
life.
4.7.1— Check Valve Clearance
Verify that engine is at ambient air temperature.
1.
Remove spark plug cable and spark plug. See
2.
Subsection 4.6 — Clean/Gap/Replace Spark Plug.
Remove six screws to release valve cover.
3.
Move piston to Top Dead Center (TDC) of com-
4.
pression stroke (both valves closed). Proceed as
follows:
a. Slowly pull handle of recoil starter while watch-
ing piston through the spark plug hole.
b. The piston moves up and down and reaches
TDC at its highest point of travel.
NOTE: Intake rocker arm is on the carburetor side,
exhaust rocker arm is on the muffler side.
Insert a 0.006 in. (0.15 mm) feeler gauge between
5.
the intake rocker arm and valve stem. The clear-
ance is correct if a slight drag is felt when sliding
the feeler gauge back and forth. Verify that clear-
ance is within the following specification:
•
Intake: 0.006 in. ± 0.0008 in. (0.15 ± 0.02mm)
Insert a 0.008 in. (0.20 mm) feeler gauge between
6.
the exhaust rocker arm and valve stem. The clear-
ance is correct if a slight drag is felt when sliding
Owner's Manual for Portable Generator
the feeler gauge back and forth. Verify that clear-
ance is within the following specification:
•
Exhaust: 0.008 in. ± 0.0008 in. (0.20 ± 0.02mm)
Proceed as follows:
7.
a. If valve clearance adjustment is required, see
Subsection 4.7.2— Adjust Valve Clearance.
b. If valve clearance is within specification, see
steps 5-8 under Subsection 4.7.2— Adjust Valve
Clearance.
4.7.2— Adjust Valve Clearance
Loosen rocker arm jam nut.
1.
Use a wrench to turn the pivot ball stud, while also
2.
using feeler gauge to check clearance between
rocker arm and valve stem.
NOTE: Hold the rocker arm jam nut in place as the
pivot ball stud is turned.
Obtain valve clearance as follows:
3.
•
Intake: 0.006 in. ± 0.0008 in. (0.15 ± 0.02mm)
•
Exhaust: 0.008 in. ± 0.0008 in. (0.20 ± 0.02mm)
When the correct valve clearance is obtained, hold
4.
the pivot ball stud with wrench to prevent rotation,
and tighten rocker arm jam nut to 69 ft-lbs (7.8 N-
m).
Recheck valve clearance to verify that it did not
5.
change during tightening of the jam nut.
Install new valve cover gasket.
6.
Start six screws to install valve cover.
7.
Verify that valve cover gasket is properly posi-
8.
tioned, and then alternately tighten screws to 20-48
in-lbs (2.3-5.4 N-m) using a crosswise pattern.
Install spark plug and spark plug cable. See Sub-
9.
section 4.6 — Clean/Gap/Replace Spark Plug.
Feeler
Gauge
Figure 4-4. Adjust Valve Clearance
Maintenance
19