Operation 37
Compressor Operation Test
Each compressor is bench tested under load at the factory to ensure proper break-in and
operation. While it is not necessary to follow any break-in procedures, complete the following
checks before putting the unit into service and periodically during use.
1
Before start-up
a) Check the compressor oil level using the sightglass on the unit. If oil is required, use only
IMT's synthetic compressor oil. Always check compressor oil level with the truck cold and
the compressor on level ground.
b) Check the air intake filter indicator (visible at the front of the compressor) for cleanliness
and obstructions. A dirty or obstructed filter may cause reduced air output. The indicator
will be in the red zone when the filter needs attention.
c) Avoid operating the compressor package when the side-to-side or front-to-rear tilt is
greater than 20°.
CAUTION
Prior to compressor start-up, make sure the cover, guards, and access plugs are in place
and secured.
2
With the compressor engaged:
a) Adjust engine speed to ensure that compressor speed does not exceed 8000 RPM
(max.) under load. Crack open air discharge valve until air pressure drops to 140 PSI
and maintains this pressure. Doing so simulates a maximum load condition.
b) If engine speed increase is required, readjust air discharge valve to 140 PSI after speed
has been increased. Repeat until appropriate compressor RPM (NOT engine RPM) is
achieved.
c) Check the compressor RPM using a phototach on the compressor input pulley, located
through the canopy cover.
