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Generac
®
Power Systems, Inc.
17
6. Start the unit by depressing and holding the
EXERCISE switch on the Power Transfer Monitor
for about ten seconds. Allow the unit to run for
exercise cycle.
7. Re-plug items needing protection back into the
Power Transfer Monitor’s switched GFCI outlet.
8. The generator is now ready for service.
3.11 ADJUSTING VALVE CLEARANCE
After the first six months, adjust the valve clearance
in the engine.
When adjusting valve clearance, the engine should be
at outdoor ambient temperature and the piston
should be at Top Dead Center (TDC) of its compres-
sion stroke (both valves closed). Correct clearance is
0.001-0.003 inch (0.03-0.07mm). Adjust valve clear-
ance as follows:
1. Loosen the rocker arm jam nut. Use an allen
wrench to turn the pivot ball stud while checking
clearance between the rocker arm and the valve
stem with a feeler gauge (Figure 3.6).
Figure 3.6 — Adjusting Valve Clearance
2. When valve clearance is correct, hold the pivot
ball stud with the allen wrench and tighten the
rocker arm jam nut with a crows foot. Tighten the
jam nut to 65-85 inch-pounds torque. After tight-
ening the jam nut, recheck valve clearance to
make sure it did not change (Figure 3.7).
Figure 3.7 — Tightening Jam Nut
3.12 GENERATOR SERVICE INTERVAL
CENTURION 3500
Annually ................................Clean Spark Arrestor
Annually..............................Change Engine Oil/filter
Every Six Months........................Clean Air Pre-filter
Annually....................................Inspect Spark Plugs
Annually................Replace Paper Air Filter Element
As Needed ................................Replace Spark Plugs
1st Six Months
Annually ..............................Adjust Valve Clearance
Section 3 – Maintenance
CENTURION 3500 Home Standby Generator