Chapter 5 Compressor Lubrication & Maintenance
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Compressor Maintenance Procedure
Maintenance intervals in the schedule outlined in this manual are based on one hour of
compressor operation equal to about 40 road miles on an engine. Thus, eight hours operation is
equal to 320 road miles, 250 hours is equal to 10,000 road miles, etc.
COMPRESSOR OIL SUMP FILL, LEVEL, AND DRAIN
Before adding or changing compressor oil, relieve all pressure from the sump. Add oil at the fill
cap located between the cooler assembly and the cab. Use the drain plug provided at the
bottom of the sump. The proper oil level, when the unit is shut down and oil has had time to
settle, is at the midpoint of the oil sightglass. The truck must be level when checking the oil. DO
NOT OVERFILL. The oil sump capacity is listed in the Compressor Specifications section.
WARNING
AVOID EQUIPMENT DAMAGE AND PERSONAL INJURY! Shut off the compressor and
manually relieve pressure from the sump before attempting to drain condensate, remove the
oil level fill plug, or break any connection in the air or oil system.
AIR INTAKE FILTER
The air intake filter is a heavy-duty two-stage dry type high efficiency filter designed to protect
the compressor from dust and foreign objects. The filter is equipped with an evacuator cup for
continuous dust ejection while operating and when stopped. Maintain the filter depending on the
dust conditions at the operating site. Service the filter element when clogged (maximum
pressure drop for proper operation is 15" H2O). The filter is equipped with a pressure drop
indicator, and the element should be changed based on the pressure drop reading first, at least
as frequently as outlined in the maintenance schedule.
AIR/OIL COALESCER
The air/oil coalescer employs an element permanently housed within a spin-on canister. This is
a single piece unit that requires replacement when it fails to remove the oil from the discharge
air, or when the pressure drop across it exceeds 15 PSI. Dirty oil clogs the element and
increases the pressure drop across it.
To replace the coalescer element:
1
Shut down compressor and wait for complete blow down (zero pressure).
2
Disconnect drain line.
3
Turn element counterclockwise for removal (viewing element from the bottom).
