Manitowoc Grove TMS9000-2 Series, Руководство по обслуживанию

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Grove
Published 01-14-2021 Control # 707-01
8-35
TMS9000-2 SERVICE MANUAL CARRIER
8
line from delivery port of the valve and install test gauge.
Place parking control valve in “release” position.
Observe that spring brake actuators release fully.
2. With parking control valve in “release” position, note
gauge pressure reading. (Correct spring brake actuator
hold-off pressure is 738 kPa (107 psi) nominally.)
3. Place parking control valve in “park” position - gauge
reading should drop to zero promptly. A lag (more than 3
seconds) in drop of pressure would indicate faulty
operation.
4. With the parking control valve in the “park” position,
gradually apply foot brake valve and note a pressure
reading increase on the gauge installed in the delivery
port.
5. Place parking control valve in “release” position.
6. Drain the reservoir, which supplies the rear service
brake circuit, apply the foot brake valve several times
and note that pressure reading on gauge decreases
each time foot brake valve is applied (spring brake
modulation). After the foot brake valve has been applied
several times, pressure on gauge will drop to the point
where release of the spring brake actuators will no
longer occur.
Leakage Test
Place the park control valve in the “release” position; using a
soap solution, coat all ports including the exhaust port. A 25
mm (1 in) bubble in 3 seconds is permitted (175 SCCM). If
the valve does not function as described, or leakage is
excessive, the valve should be replaced with a new or
remanufactured unit.
Dual Brake Valve
Removal
1. Chock the wheels and completely depressurize both air
systems.
2. Tag and disconnect all air lines connected to the brake
valve.
3. Remove the nuts, washers, and lockwashers securing
the valve to the mounting studs and remove the brake
valve and pedal assembly.
Installation
1. Position the brake valve and pedal assembly onto the
studs under the front console and secure with the nuts,
washers, and lockwashers.
2. Connect all the air lines to the brake valve as per
removal tag.
Operating Test
1. Check the delivery pressure of both #1 and #2 circuits
with a test gauge. Depress the treadle to several
positions between fully released and applied. Check the
pressure on the gauges to see if it varies equally and
proportionately with the movement of the brake pedal.
2. After the brakes are released, the reading on the test
gauges should fall to zero. The delivery pressure in #1
circuit should be 30 kPa (4 psi) greater than #2 circuit
with both supply reservoirs at the same pressure.
Leakage Test
1. Make and hold a high pressure application 550 kPa (80
psi).
2. Coat the exhaust port and body of the brake valve with a
soap solution. A leakage of a 25 mm (1 in) bubble in
three seconds is permitted.
Preventive Maintenance
Every 300 operating hours, 16,000 km (10,000 mi), or three
months.
1. Clean dirt away from the heal of the treadle, plunger
boot, and mounting plate.
2. Lubricate the treadle roller, hinge pin, and roller pin
using a barium base lubricant.
3. Check the rubber plunger boot for deterioration and
replace as necessary.
4. Lubricate the plunger with a barium base lubricant.
Every 3600 operating hours, 16,000 km (10,000 mi), or
yearly.
Replace inlet and exhaust valves, exhaust diaphragm, O-
rings, and rubber graduating spring if worn or deteriorated.
Every 7200 operating hours, 32,000 km (20,000 mi) or two
years.
WARNING
Death or Injury Could Occur!
Do not attempt to disassemble the valve. The valve
contains high spring forces that could result in personal
injury if disassembly is attempted!
CAUTION
Damage Could Occur!
A change in braking characteristics or low air pressure
may be an indication of a malfunction in one of the brake
circuits. Do not operate the vehicle until repairs have been
made and both circuits are operating properly. Always
check brakes after servicing.
Fo
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Reference
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