TM 5-3810-307-24-1-2
Oil Supply: Engine oil supply is provided either internally or
externally to the compressor. Flange mount models can
have internal or external oil supply sources, while base
mount models are provided with external oil supply only.
When an external supply is used, a minimum of 3.18 mm
[0.125 in] inside diameter (ID) line size must be used to
provide adequate oil flow.
The supply line must be free of sharp bends or kinks which
can cause flow restrictions. The oil supply source must be
taken immediately after oil filtration from the engine for best
results.
Oil Change Interval: Use the oil drain interval specified for
a particular engine model. The use of a high quality SAE
15W40 heavy duty engine oil which meets the American
Petroleum Institute (API) performance classifications CE or
CF-4 is recommended.
NOTE
When operating in extreme environments
where very high or very low temperatures or
airborne dirt or dust is present, consider
much shorter oil change intervals consistent
with engine manufacturer recommendations.
Oil Drain: Compressor oil drainage is critical to prevention
of oil consumption. Flange mount compressor models
provide either internal or external oil drainage. Base mount
model provides external oil drainage only.
A 12.7 mm [0.50-inch] ID size is required when using an
external oil drain. Using a smaller line size, or less than
12.7 mm [0.50-inch] fittings, can cause excessive oil build-
up in the compressor crankcase. The potentially damaging
results include crankcase pressurization and oil passage
into the vehicle's air system.