Grove Published 11-10-2014, Control # 524-00 2-23
RT880E SERVICE MANUAL HYDRAULIC SYSTEM
Procedure D - Set Service Brake
Accumulator Charge Valve Limits - Check/
Adjust
1. With the engine off, discharge all of the pressurized oil
stored in the accumulators by depressing the service
brake pedal on the cab floor 4 to 6 times or until the
pedal has no back pressure.
2. Install a pressure check diagnostic coupler with gauge
onto the diagnostic nipple at “A1” port of the Dual
Accumulator Charging Valve (see Figure 2-13).
3. Start engine and idle. The charging valve will
immediately start to charge the accumulators. Watch the
pressure gauge. The high charge limit pressure should
read 2320 psi +72/-145 when the pressure gauge stops
rising.
4. With the engine still running at idle, repeatedly depress
service brake pedal on the cab floor until the gauge
pressure approaches 2100 psi. Watch the gauge closely
and push the brake pedal again to recharge. The low
charging limit should be 1950 psi ±145 when it starts to
recharge. Replace the valve if the pressures are not
within the specified range.
5. Stop engine. Remove diagnostic couplers and
reconnect plumbing.
Procedure E - Accumulator Pre-Charge
Pressure - Check
1. With the engine off, discharge all of the pressurized oil
stored in the accumulators by depressing the service
brake pedal on the cab floor 4 to 6 times or until the
pedal has no back pressure. Remove the gas valve
guard and cap on the accumulator (see Figure 2-14).
2. Before attaching the gas charging assembly onto the
gas valve, back the gas chuck “T” handle all the way out
(counterclockwise).
3. Close the charging assembly bleed valve. Attach the
swivel nut onto the gas valve and tighten (10 to 15 lb-in).
4. Turn the gas chuck “T” handle all the way down
(clockwise) which will depress the core in the gas valve.
5. Check the pre-charge pressure. It should be 1500 to
1550 psi.
6. If the pressure is 1500 to 1550 psi, remove the charging
valve assembly by turning the “T” handle all the way out
on the gas chuck and then opening the bleed valve (see
Figure 2-14).
7. Secure the gas valve, loosen the swivel nut and remove
the charging assembly. Replace the gas valve cap and
guard.
Procedure F - Pre-Charging the Accumulator
1. With the engine off, discharge all of the pressurized oil
stored in the accumulators by depressing the service
brake pedal on the cab floor 4 to 6 times or until the
pedal has no back pressure. Remove the gas valve
guard and cap on the accumulator (see Figure 2-14).
2. Ensure that the nitrogen supply bottle is shut off, then
attach the charging valve assembly to it.
3. Before attaching the charging assembly to the
accumulator gas valve, back the gas chuck “T” handle
all the way out (counterclockwise).
4. Close the charging assembly bleed valve. Without
looping or twisting the hose, attach the swivel nut to the
accumulator gas valve and tighten (10 to 15 lb-in).
5. Turn the gas chuck “T” handle all the way down
(clockwise) which will depress the core in the gas valve.
6. Crack the nitrogen bottle valve and slowly fill the
accumulator. Shut off the valve when the pre-charge is
1500 to 1550 psi.
7. If the pre-charge pressure is higher than specified in
step #6, close the nitrogen bottle valve and slowly open
the bleed valve on the charging assembly (see
Figure 2-14) until the pressure is to specification.
8. Remove the charging assembly by turning the “T”
handle all the way out (counterclockwise) on the gas
chuck and then open the bleed valve.
9. Secure the gas valve, loosen the swivel nut and remove
the charging assembly. Replace the gas valve cap and
guard.
Procedure G - Front Steer Pressure - Check/
Adjust
1. Install pressure check diagnostic quick disconnect with
gauge onto test port at GP7 port of the Front Steer,
Swing and Accessory Manifold (see Figure 2-9).
2. Start engine and throttle up to full RPM. Fully turn the
steering wheel to left or right against the axle stop.
Adjust the priority flow control relief valve in the Front
Steer, swing and Accessory Manifold (see Figure 2-9) by
removing the adapter and hose in the end of the
cartridge to access the hex adjustment screw and adjust
“in” to increase or “out” to decrease so that a gauge
pressure of 2600 psi ±50 is achieved.
3. Stop engine. Remove diagnostic couplers.
To Next Page
Loading...
Need help?
General
