Maintenance
Owner’s Manual for 60 Hz Air-Cooled Generators
27
Valve Clearance Adjustment
IMPORTANT NOTE: Contact an IASD for service
assistance. Proper valve clearance is essential for
prolonging the life of the engine.
Check valve clearance after the first 25 hours of
operation, then after 400 hour intervals. Adjust if
necessary.
Check Valve Clearance
NOTE:
The engine should be cool before checking valve
clearance. Adjustment is not needed if valve clearance is
within the dimensions provided in
1.
Close fuel valve and disconnect battery.
2.
Remove spark plug wire(s), and position wire(s)
away from plug(s).
3.
Remove spark plug(s).
4.
Remove the four screws attaching the valve cover.
Remove and discard the gasket. (Repeat for
second cylinder, if equipped.)
5.
Verify the piston is at top dead center (TDC) of its
compression stroke (both valves closed).
NOTE:
To move the piston to TDC, remove the intake
baffle 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.
See
. Check the valve clearance
between each rocker arm (E) and valve stem (F)
with a feeler gauge.
Figure 4-4. Valve Clearance Adjustment
7.
Install replacement valve cover gasket(s).
8.
Install valve cover(s). Tighten fasteners in a cross
pattern, torquing to:
Adjust Valve Clearance
See
. Proceed as follows to adjust valve
clearance:
NOTE:
Allow engine to cool before adjusting valve
clearance.
1.
Remove spark plug wire(s) and position wire(s)
away from plugs.
2.
Remove spark plug(s).
3.
Remove the four screws attaching the valve cover.
Remove and discard gasket.
4.
Verify piston is at top dead center (TDC) of its
compression stroke (both valves closed).
5.
Loosen the rocker jam nut (C).
6.
Turn the pivot ball stud (D) using a 10 mm hex key
while checking clearance between the rocker arm
(E) and the valve stem (F) with a feeler gauge.
Adjust clearance as per
.
NOTE:
Hold the rocker jam nut in place as the pivot ball
stud is turned.
7.
Hold the pivot ball stud (D) in place with a wrench
and tighten the rocker arm jam nut. Tighten the jam
nut according to the following torque specifications:
8.
Inspect 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:
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.
Attach the spark plug wire to the spark plug.
13.
Repeat the process for the other cylinder if
necessary.
(000130)
WARNING
Accidental Start-up. Disconnect the negative battery
cable, then the positive battery cable when working
on unit. Failure to do so could result in death
or serious injury.
002380
F
C
E
D
16 and 22kW
60
in-lbs
(6.8 Nm)
16 and 22kW
174
in-lbs
(19.68 Nm)
16 and 22kW
60
in-lbs
(6.8 Nm)