Terex TS14G, Maintenance Manual

Page: 277 / 376

Section 250-0070
SM 1755 Rev1 04-04
3
Braking System - Treadle Valve
1. Position the vehicle in a level work area, apply the
parking brake and switch off the engine.
2. Operate the steering in both directions several times
to relieve any pressure in the steering system. Block
all road wheels.
3. Open drain cocks on air tanks and drain air from four
main tanks and auxiliary air tank. Close drain cocks on
air tanks when air is exhausted.
4. Ensure all air lines connected to the treadle valve
are identified for ease of installation and disconnect air
lines from the treadle valve assembly.
5. Remove electrical connection to stop light pressure
switch.
6. Release and remove mounting hardware securing
treadle valve assembly to the cab floor.
7. Remove treadle valve assembly from the vehicle.
8. If required, separate valve body (26 & 31) assembly
and treadle (1) assembly.
Note:
The treadle valve assembly should not be
disassembled further as replacement of parts is by
treadle (1) assembly and/or valve body (26 & 31)
assembly only. Refer to 'Maintenance' procedures.
ASSEMBLY AND INSTALLATION
Numbers in parentheses refer to Fig. 1.
Note: Tighten all fasteners to standard torques listed in
Section 300-0080, STANDARD BOLT AND NUT
TORQUE SPECIFICATIONS.
1. If removed, install treadle (1) assembly on valve
body (26 & 31) assembly.
2. Secure treadle valve assembly to the cab floor with
mounting hardware, as removed at 'Removal and
Disassembly'.
3. Install all air lines to the treadle valve assembly, as
tagged at removal.
4. Connect electrical connection to stop light pressure
switch.
5. Start the engine and allow air pressure in the tanks
to build up to correct operating pressure. Check for
leaks at air lines and tighten as required.
6. Remove wheel blocks from all road wheels.
ADJUSTMENTS
Numbers in parentheses refer to Fig. 1.
If the treadle valve does not release promptly or does
not fully release, it indicates that exhaust valve is not
opening sufficiently. This can be caused by:
1. Lack of lubrication in valve body causing piston and
spring assembly to bind.
2. Dirt or other foreign matter between the heel of
treadle (1) and mounting plate (17).
If the treadle valve does not apply promptly, or does
not apply fully, it indicates that inlet valve (5) is
not opening sufficiently. Check for correct operation
and replace valve assembly, if required.
Courtesy of Machine.Market