Remove the air accessory air lines from the air compressor governor and install pipe plugs in the air governor unloader ports.
Operate the engine to activate the air compressor.
If the air compressor stops pumping (air pressure stops rising) at the governed air pressure, there is a leak in an accessory or an accessory air line. Refer to the equipment manufacturer’s instructions for troubleshooting and repair.
If the air compressor does not stop pumping (air pressure continues to rise) at the governed air pressure, connect a regulated shop air pressure line to the air compressor unloader valve port.
Apply 690 kPa [100 psi] air pressure to the unloader port.
If the air compressor stops pumping (air pressure stops rising), the air governor is malfunctioning and must be repaired or replaced, or the air governor mounting gasket is leaking. Refer to the manufacturer’s instructions.
If the air compressor continues to pump (air pressure continues to rise), the unloader valve is malfunctioning and must be replaced. Refer to Air Compressor Unloader Valve, Procedure 012-013.
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