COMPLAINTS COMMON TO THE CHARGING & AIR SUPPLY SYSTEM
Complaint: System Pressure Goes to 150+ psi
•Drain the air system to zero (0) psi, remove/disconnect the governor from the compressor. Start the engine and note the air pressure rise on the dash gauges. Apply 120 psi of shop air to compressor unloader port. If the air pressure continues to rise, repair compressor unloaders or replace compressor. If air ceases to rise, repair or replace governor.
Complaint: Low Pressure Warning After Only 1 or 2 Applications
•Brakes out of adjustment: adjust brakes.
•Excessive system leakage on the service (application) side of system: Build the system pressure to 120 psi and turn the engine off. With the park brakes released, make a full service application and note the dash gauges for two (2) minutes. A pressure drop on either gauge should not exceed 4 psi. (two (2) psi per min.)
If the pressure drop is excessive, find the leakage in service system, if OK, then proceed to next complaint.
•Incorrect low pressure switch in use or setting incorrect: Build the system pressure to 120 psi, with the engine OFF and the ignition ON, slowly drain the air pressure from one service reservoir. Low pressure warning on at minimum 60 psi, maximum
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