Manitowoc Grove RT770E Service Maintenance Manual

2-11
GROVE
RT770E HYDRAULIC SYSTEM
2
Published 11/26/2014, Control # 447-05
2. Slow response. a. Low hydraulic oil level. a. Check system for leaks. Make repairs
as needed. Fill reservoir.
b. Hydraulic oil temperature too high
(watery thin oil) or too low (thick
sluggish oil).
b. If too low, warm up system. As
needed, troubleshoot cooler circuit. If
too high, troubleshoot cooler circuit.
Likely suspects are in-line check
valve and related hydraulic circuits.
c. Faulty pump section(s). c. Repair or replace pump section(s) or
entire pump.
3. Pump noise
accompanied by
hydraulic oil
foaming in
reservoir.
a. Low hydraulic oil level. a. Check system for leaks. Make repairs
as needed. Fill reservoir.
b. Excessive engine speed. b. Regulate engine speed.
c. Air entering at suction lines. c. Check all lines for security and proper
repair. Tighten, repair, or replace as
needed.
4. Excessive
pressure buildup.
a. System relief valve set too high. a. Using adequate pressure gauge,
adjust system relief valve as
necessary.
b. Restricted pump-to-control
valve supply line.
b. Clean, repair, or replace line as
necessary.
5. Specific hydraulic
system (lift, hoist,
telescope, swing)
not working.
a. Leak in system. a. Check system for leaks. Make repairs
as needed. Fill reservoir.
b. Faulty hydraulic remote control valve. b. Adjust or replace valve.
c. Faulty directional control valve. c. Replace valve.
d. Poorly adjusted control in circuit. d. Troubleshoot circuit with schematic.
Adjust hydraulic component per
schematic.
e. Faulty hydraulic cylinder, motor, or
valve.
e. Replace faulty component.
Symptom Probable Cause Solution

Manitowoc Grove RT770E Specifications

General

Brand	Manitowoc
Model	Grove RT770E
Category	Construction Equipment
Language	English