GILLIG LOW FLOOR, Руководство по обслуживанию

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Air System
Performance Testing
Test the vehicle air system as follows:
1. Bleed the vehicle air system reservoir gauges down (apply brakes several times) to approximate-
ly 85 psig.
2. With the engine running at full governed speed (no load, no air accessories being used), the com-
pressor should reach governor cut-out pressure (130 psi), then unload.
If the compressor does not reach governor cut-out pressure, check for air leaks in the system. If
reservoir volume and engine RPM are per original vehicle manufacturer’s specifications, system
plumbing leakage must be checked and, if necessary, repaired. See air system leakage test proce -
dures which follow.
If the compressor fails to unload, verify proper governor operation.
Air System Leakage Test
1. Park your bus on a level surface. Leave engine on.
2. Chock the wheels to prevent movement, then release the parking brake.
3. Build up air tank pressure to governor cut-out pressure (130 psi).
4. Turn engine off.
5. Let air pressure gauges stabilize for 1 minute. After 1 minute, time the pressure drop rate on the
gauges.
Pressure should not drop more than 2 psi per minute with the service brakes released.
Pressure should not drop more than 3 psi per minute with a 90 psi service application.
If pressure drop is excessive, make the necessary repairs.
Listen for air leaks. Soapy water or high frequency acoustic detectors may be used to detect air
leaks.