• Add recommended coolant mixture as necessary.
• Periodically remove radiator pressure cap to make
sure the coolant recovery system is functioning
properly. Coolant should be at bottom of radiator
filler neck. If coolant level is low, inspect gasket in
radiator pressure cap. Replace cap, if necessary.
To have pressure cap tested, contact an authorized
service dealer. Inspect cooling system and coolant
recovery system for leaks.
OPERATOR CAN PERFORM
4.5.1 CHECK ENGINE OIL LEVEL
Refer to "Checking Fluid Levels" in Section 4.4.
4.5.2 CHECK BATTERY
• Check battery fluid level each week as outlined
under "Check Fluid Levels".
• Check battery cables for condition, tightness, cor-
rosion or damage. Clean, tighten or replace as
4.5.3 EXERCISE SYSTEM
If the unit is not set up for automatic operation, start
the generator engine at least once every seven days
and let it run at least 12 minutes. See Section 3.6,
"Weekly Exercise Cycle".
4.5.4 INSPECT COOLING SYSTEM
• Inspect engine cooling system at least once each
• Check hoses for damage, deterioration, leaks, etc.
Correct any discrepancies found.
• Check hose clamps for tightness.
4.5.5 CHECK ENGINE COOLANT LEVEL
See "Checking Fluid Levels" in Section 4.4.
4.5.6 PERFORM VISUAL INSPECTION
Complete a thorough visual inspection of the entire
engine-generator monthly. Look for obvious damage,
loose, missing or corroded nuts, bolts and other fas-
teners. Look for fuel, oil or coolant leaks.
4.5.7 INSPECT EXHAUST SYSTEM
Inspect the exhaust system at least once every three
months. Check all exhaust system pipes, mufflers,
clamps, etc. for condition, tightness, leaks, security,
Section 4 — Maintenance
Guardian 40kW Liquid-cooled Generators
4.5.8 CHECK FAN BELT
• Inspect fan belts every three months. Replace any
damaged, deteriorated, worn or otherwise defec-
• Check fan belt tension. Thumb pressure, exerted
midway between pulleys, should deflect about 3/8
to 3/4 inch. Adjust belt tension as required.
4.5.9 INSPECT ENGINE GOVERNOR
Visually inspect electronic governor.
DANGER: Do not attempt to adjust the gover-
nor. Only qualified service dealers 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.
4.5.10 CHANGING ENGINE OIL
Refer to maintenance performed by authorized service
dealers 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
4. Turn OIL FILTER (Figure 4.2) counterclockwise
and remove. 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 OVERTIGHTEN.
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
Power Systems, Inc. 17