Manitowoc Grove GRT880 Service Manual

HYDRAULIC SYSTEM GRT880 SERVICE MANUAL
2-12
Published 10/19/2017, Control # 618-00
Troubleshooting
Symptoms and Solutions
Symptom Probable Cause Solution
1. No hydraulic oil
flows in systems.
a. Low hydraulic oil level. a. Check system for leaks. Make repairs
as needed. Fill reservoir.
b. Reservoir-to-pump suction lines
broken or restricted. Air entering at
suction lines. Pump not priming.
b. Clean, repair, or replace lines as
necessary. Check lines for security,
absence of cracks, and proper
attachment. Tighten, repair, or
replace parts as necessary.
c. Pump shaft sheared or disengaged. c. If drive shaft is damaged or sheared,
remove and repair or replace as
necessary
d. Internal contamination. d. Drain, flush with recommended oil
mixture, then drain and refill system
with recommended hydraulic oil.
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. c. Repair or replace 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.
Reference Only

Manitowoc Grove GRT880 Specifications

General

Brand	Manitowoc
Model	Grove GRT880
Category	Construction Equipment
Language	English