Manitowoc National Crane NBT40 Series, Service Manual

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HYDRAULIC SYSTEM NBT40 SERVICE MANUAL
2-14
Published 8-01-2017 Control # 287-11
Figure 2-7 Table
3. Start engine and set throttle to governed rpm.
4. Activate the function for the selected outrigger hydraulic
line and adjust the flow control relief valve (1, Figure 2-8)
on the hydraulic pump manifold to 20684 kPa ±689
(3000 ±100 psi).
5. Shutdown the engine and disconnect the pressure
gauge and reconnect the hydraulic line.
Swing Valve Relief
NOTE: Do not rely on the swing brake to hold the turret in
place when checking relief pressures, as the turret
may push through the swing brake. Always check
pressures by removing and plugging the hydraulic
hoses at the swing motor.
1. Disconnect the two work port hoses from the swing
motor and cap the swing brake motor ports.
2. Plug one hose and install a gauge in the other hose.
3. Start engine and set throttle to governed rpm.
4. Activate the swing function and check for a pressure of
21373 kPa +689 -0 (3100 +200 - 0 psi).
5. Shut down the engine.
6. Remove the gauge from the one hose and install in the
other hose. Plug the remaining open hose.
7. Start engine and set throttle to governed rpm.
8. Activate the swing function and check for a pressure of
21373 kPa +689 - 0 (3100 +200 - 0 psi).
9. Shut down the engine.
10. Replace swing relief valve(s) in the swing control valve
(Figure 2-4) if pressure measured is not within
specification.
Center Front Stabilizer (if equipped)
1. Disconnect the front stabilizer retract (1, Figure 2-9) and
extend lines (2). Cap the retract line (1) and install a
gauge in the extend line (2).
NOTE: Install a gauge in each line and set the extend and
retract pressures as described below with extend/
retract switch.
2. Start engine and set at governed rpm.
3. Depress the front outrigger extend/retract switch to
extend.
4. Adjust the extend relief valve (4, Figure 2-9) on the front
stabilizer port block to
3447 kPa +689/-0 (500 psi +100/-0).
5. Shut down the engine.
6. Remove the gauge from the extend line and install in the
retract line. Cap the extend line.
7. Adjust the retract relief valve on the front stabilizer port
block to 12065 kPa +689/-0 (1750 psi +100/-0)
8. Shutdown the engine, remove the gauge and cap, and
reconnect the SFO hydraulic lines.
Item Description
1 Outrigger
2 Jack Cylinder - down
3 Bean Extension - out
4 Jack Cylinder/Bean Extension - up/out
FIGURE 2-7
2
3
4
1
FIGURE 2-8
1
7599
Reference Only