Generac
®
Power Systems, Inc.
19
4.8.8 CHECK FAN BELT
• Inspect fan belts every three months. Replace any
damaged, deteriorated, worn or otherwise defec-
tive belt.
• Check fan belt tension. Thumb pressure, exerted
midway between pulleys, should deflect about 3/8
to 5/8 of an inch. Adjust belt tension as required.
4.8.9 INSPECT ENGINE GOVERNOR
Visually inspect electronic governor.
DANGER: Do not attempt to adjust the gover-
nor. Only qualified service facilities should
adjust the governor. Excessively high operat-
ing speeds are dangerous and increase the
risk of personal injury. Low speeds impose a
heavy load on the engine when adequate
engine power is not available and may short-
en engine life. Correct rated frequency and
voltage are supplied only at the proper gov-
erned speed. Some connected electrical load
devices may be damaged by incorrect fre-
quency and/or voltage. Only qualified service
technicians should adjust the governed speed.
4.8.10 CHANGING ENGINE OIL
Refer to maintenance performed by authorized service
facilities for engine oil and filter change frequencies.
Drain the oil while the engine is still warm from run-
ning. This means warm up the engine, shut it down
and drain immediately as follows:
1. Remove OIL DRAIN HOSE from its retaining clip.
2. Loosen and remove OIL DRAIN HOSE CAP. Drain
oil completely into suitable container.
3. When all oil has drained, install and tighten OIL
DRAIN HOSE CAP, and re-install into its retaining
clip.
4. Turn OIL FILTER (Figure 4.1) counterclockwise
and remove. Properly dispose of old filter.
5. Apply light coating of new engine oil to seal of new
oil filter. Install FILTER and tighten by hand only.
DO NOT OVER TIGHTEN.
6. Remove OIL FILL CAP. Add recommended oil (see
SPECIFICATIONS). DO NOT FILL ABOVE THE
DIPSTICK “FULL” MARK. Crankcase oil capacity
is 4.0 U.S. quarts (3.8 liters).
After refilling the crankcase with oil, always
check oil level on dipstick. NEVER OPERATE
ENGINE WITH OIL BELOW THE DIPSTICK
“ADD” MARK.
7. Start engine and check for oil leaks.
4.8.11 CHANGING THE ENGINE AIR CLEANER
To replace the engine air cleaner, (part number
059402), simply remove the air cleaner cover and
replace the air filter making sure it is positioned
properly before reattaching the cover (Figure 4.1).
See the “Service Schedule,” for air cleaner mainte-
nance.
4.8.12 SPARK PLUGS
Reset the spark plug gap or replace the spark plugs
as necessary (Figure 4.4). See Section 6.
1. Clean the area around the base of the spark plugs
to keep dirt and debris out of the engine. Clean by
scraping or washing using a wire brush and com-
mercial solvent. Do not blast the spark plugs to
clean.
2. Remove the spark plugs and check the condition.
Replace the spark plugs if worn or if reuse is
questionable. See the “Service Schedule,” Section
6, for recommended inspection.
3. Check the spark plug gap using a wire feeler
gauge. Adjust the gap to 1.07-1.17 mm (0.042-
0.046 inch) by carefully bending the ground elec-
trode (Figure 4.2).
Figure 4.4 – Setting the Spark Plug Gap
4.8.13 COOLANT CHANGE
Every year, have an Authorized Service Facility drain,
flush and refill the cooling system. See
“Specifications” for cooling system recommenda-
tions.
!
!
DANGER
Section 4 — Maintenance
Guardian Liquid-cooled 25 kW Generator
SET PLUG GAP AT 1.07 - 1.17 mm
(0.042 - 0.046 inch)
