GILLIG LOW FLOOR, Service Manual

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Air System
Removal
Refer to Figures 6-27 and 6-28 for item numbers referenced in parenthesis.
removal of the retarder control Assembly
1. Chock the vehicle wheels or park the vehicle by mechanical means. (Block and hold vehicle by
means other than air brakes.) Drain all air system reservoirs.
2. Disconnect the plug of the electrical cable from its mating socket of the vehicles power supply.
3. Identify and disconnect all air supply and delivery lines at the brake valve, if brake valve replace-
ment is required.
4. Remove the brake valve and treadle assembly from the vehicle by removing the three cap screws
on the outer bolt circle of the mounting plate.
NOTE: Before removing the treadle assembly, be sure to mark the position of the treadle mount -
ing plate relative to the retarder control assembly.
5. Remove the treadle from the mounting plate by tapping out the roll pin and then the pin retaining
the treadle, spring and mounting plate.
NOTE: Mark the position of the retarder control assembly to the upper valve housing.
6. Remove the boot from the plunger.
7. Remove the three remaining cap screws (2) from the mounting plate. Separate the mounting plate
from the retarder control section (1) and the retarder control section from the upper valve hous-
ing (13).
Do not separate the upper valve housing from the balance of the brake
valve. Keep the plunger in the retarder control section in its bore. Switch
damage will result from attempted removal or permitting it to slide out
of the body/bore by more than 3/8".
Disassembly
Refer to Figures 6-27 and 6-28 for item numbers referenced in parenthesis.
1. If the entire brake valve and treadle assembly was removed from the vehicle, remove the three
cap screws securing the treadle assembly to the basic brake valve.
2. Remove the screw (15) securing the exhaust diaphragm (17) and washer (16) to the exhaust
cover (18).
3. Remove the four screws that secure the exhaust cover (18) to the lower body.
4. Remove the secondary inlet and exhaust valve assembly (19) from the lower body.
5. Remove the four hex head cap screws securing the lower body to the upper body and separate the
body halves.
6. Remove the rubber seal ring (21) from the lower body.