Manitowoc Grove GRT880 Service Manual

8-7
GRT880 SERVICE MANUAL UNDERCARRIAGE
8
Published 10/19/2017, Control # 618-00
GROVE
STEERING SYSTEMS
Description
To maximize maneuverability, the crane can be steered by
the front axle, the rear axle, or by the front and rear axles
simultaneously. The crane utilizes two separate steering
systems, one to control front axle steering and one for rear
axle steering.
Front Steering System
The front steering system consists of a load sense steer
priority flow valve (part of the accessory manifold valve), load
sense steering control valve, and two steer cylinders. Refer
to Accessory Manifold Valve, page 2-52 for a description of
the front steer hydraulic components, their function, and
maintenance information.
Rear Steering System
The rear steering system consists of a three-position, dual
solenoid controlled directional valve; two cross-port check
valves; and two steer cylinders. Refer to Carrier Combination
Manifold Valve, page 2-57 for a description of the rear steer
hydraulic components, their function, and maintenance
information. A rear steer indicator system is provided to
indicate when the rear wheels are not centered. This system
consists of an indicator light located on the front console in
the cab and a switch located on the left side of the rear axle.
When the rear wheels are turned to the left or right, the
amber indicator light will illuminate.
Secondary Steering System (CE Units)
The secondary steering system is provided to back up the
normal front steering system if loss of hydraulic flow occurs
due to pump or engine failure. The system consists of two
hydraulic accumulators; a pilot-operated, two-position
control valve; one check valve; and a pressure switch, which
receive hydraulic oil flow from the service brake dual-
accumulator charge valve to supplement the normal front
steer circuit.
Maintenance
Front Steering System
Troubleshooting
Table 8-1
Symptom Probable Cause Solution
1. Hard to steer left and
right.
a. Hydraulic oil low. a. Check system for leaks. Make
repairs as needed. Fill reservoir.
b. Clogged or loose hydraulic lines or
fittings.
b. Clean or tighten lines or
fittings.
c. Defective flow divider valve(s). c. Repair or replace valve(s).
d. Defective steering control valve. d. Repair or replace valve.
e. Defective hydraulic pump. e. Repair or replace pump.
2. Hard to steer either left
or right.
a. Clogged or loose hydraulic lines or
fittings.
a. Clean or tighten lines or
fittings.
b. Defective steer cylinder. b. Repair or replace cylinder.
3. Steering is erratic left
and right.
a. Hydraulic oil low. a. Check system for leaks. Make
repairs as needed. Fill reservoir.
b. Clogged or loose hydraulic lines or
fittings.
b. Clean or tighten lines or
fittings.
c. Defective steering control valve. c. Repair or replace valve.
d. Defective hydraulic pump. d. Repair or replace pump.
Reference Only

Manitowoc Grove GRT880 Specifications

General

Brand	Manitowoc
Model	Grove GRT880
Category	Construction Equipment
Language	English