GILLIG LOW FLOOR, Руководство по обслуживанию

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Air System
Figure 6-43, Park Application
operation-parking
See Figure 6-43 . If both the primary and secondary air
systems are intact and the park control valve (PP-1)
is placed in the “park” or exhaust position, the SR-1’s
supply of air pressure and the air pressure in the spring
brake actuator cavities is exhausted. The single check
valve in the SR-1 assists this exhausting of air pressure
from the spring brake by allowing the air below piston
B to flow back out the open exhaust of the park control
valve. When air pressure below piston B has dropped
sufficiently, piston B moves down, opening the inlet of
valve B, thus providing an additional exhaust passage
for air exhausting through the SR-1 from the spring brakes.
SR- Preventive Maintenance
Every 100,000 miles, 12 months, or 3600 operating hours, disassemble the SR-1 and clean all parts and
mineral spirits. Replace all rubber parts and any worn or damaged components. Contact your Gillig parts
representative at (800) 735-1500 for Bendix-approved rebuild kits or parts for this valve.
SR- Service Checks
operation check
First, block the vehicle and hold by means other than the vehicle brakes. Charge the air brake system to
governor cut-out pressure (130 ±5 psi).
1. Pull up on the park brake valve to apply the parking brake. Check to make sure that the spring
brake actuators apply promptly. In the delivery port of the SR-1 valve, install a test gauge known
to be accurate. Place the parking control valve in the “release” position (push down on it). Check
to see that the spring brake actuators release fully.
2. With the park brake control valve in the “release” position, note the gauge pressure reading.
It should read approximately 100 psi. If the pressure reading is incorrect, repair or replace the
SR-1.
3. Place the park brake valve back in the “park” position. The gauge reading should immediately
drop to zero. A slow release of pressure may indicate faulty operation of the single check valve
(within the modulating valve).
4. Place the parking control valve in the “release” position. Completely drain the primary air tank.
Apply the foot brake (E-8) several times and note that the pressure reading on the gauge decreases each
time the foot brake is applied. After several applications, pressure on the gauge will drop to the point
where release of the spring brake actuators will no longer occur.