Valve Clearance Adjustment; Check Valve Clearance; Adjust Valve Clearance - Generac Power Systems 8 kVA Owner's Manual

Figure 4-4. Spark Plug Gap Measurement

Valve Clearance Adjustment

Check the valve clearance after the first 25 hours of
operation, then after 400 hour intervals. Adjust if
necessary.
Important: Please contact an IASD for service
assistance. Proper valve clearance is essential for
prolonging the life of the engine.

Check Valve Clearance

NOTE: The engine should be cool before checking the
valve clearance. Adjustment is not needed if valve
clearance is within the
Specifications.
1. Close fuel valve and disconnect battery to avoid
accidental start-up.
2. Remove spark plug wires, and position wires away
from plugs.
3. Remove spark plugs.
4. Remove the four screws attaching the valve cover.
Remove and discard gasket.
5. Make sure the piston is at top dead center (TDC) of
its compression stroke (both valves closed). To
move the piston to TDC, remove the intake screen
at the front of the engine to access the flywheel
nut. Use a large socket and socket wrench to
rotate the flywheel nut clockwise, which will rotate
the crankshaft. Watch the piston through the spark
plug hole. The piston should move up and down.
The piston is at TDC when it is at its highest point
of travel.
6. Check the valve clearance between the rocker arm
and valve stem with a feeler gauge.
7. Install replacement valve cover gasket.
8. Install valve cover. Tighten fasteners in a cross
pattern, torquing to 60 in-lbs. (6.8 Nm).

Adjust Valve Clearance

See Figure 4-5. Proceed as follows to adjust the valve
clearance:
Owner's Manual for 50 Hz Air-Cooled Generators
000211
dimensions provided
NOTE: Allow engine to cool before adjusting valve
clearance.
1. Remove spark plug wires and position wires away
from plugs.
2. Remove spark plugs.
3. Remove the four screws attaching the valve cover.
Remove and discard gasket.
4. Make sure the piston is at top dead center (TDC) of
its compression stroke (both valves closed).
5. Loosen the rocker jam nut (C) 13 mm wrench.
.
E
C
Figure 4-5. Valve Clearance Adjustment
in
6. Turn the pivot ball stud (D) using an 10 mm Allen
wrench while checking clearance between the
rocker arm (E) and the valve stem (F) with a feeler
gauge. Adjust clearance as per Specifications.
NOTE: Hold the rocker arm jam nut in place as the pivot
ball stud is turned.
7. When valve clearance is correct, hold the pivot ball
stud (B) in place with a wrench and tighten the
rocker arm jam nut. Tighten the jam nut to 174 in
lbs (19.68 Nm)
8. After tightening the jam nut, recheck valve
clearance to verify it did not change.
9. Install new valve cover gasket.
10. Install the valve cover. Tighten fasteners in a cross
pattern, torquing to 60 in-lbs (6.8 Nm).
NOTE: Start all four screws before tightening, or it will
not be possible to get all the screws in place. Verify the
valve cover gasket is in place.
11. Install spark plugs and torque to 18 ft-lbs (25 Nm).
12. Reattach the spark plug wire to the spark plug.
13. Repeat the process for the other cylinder if
necessary.
Maintenance
D
F
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