CONTENTS
SECTION 1 GENERAL
Group 1 Safety hints
1-1
Group 2 Specifications
1-5
Group 3 Periodic replacement
1-13
SECTION 2 REMOVAL AND INSTALLATION OF UNIT
Group 1 Structure
2-1
Group 2 Removal and Installation of Unit
2-2
SECTION 3 POWER TRAIN SYSTEM
Group 1 Structure and operation
3-1
Group 2 Troubleshooting
3-24
Group 3 Disassembly and assembly
3-28
SECTION 4 BRAKE SYSTEM
Group 1 Structure and function
4-1
Group 2 Operational checks and troubleshooting
4-15
Group 3 Tests and adjustments
4-18
SECTION 5 STEERING SYSTEM
Group 1 Structure and function
5-1
Group 2 Operational checks and troubleshooting
5-11
Group 3 Disassembly and assembly
5-13
SECTION 6 HYDRAULIC SYSTEM
Group 1 Structure and function
6-1
Group 2 Operational checks and troubleshooting
6-15
Group 3 Disassembly and assembly
6-19
SECTION 7 ELECTRICAL SYSTEM
Group 1 Component location
7-1
Group 2 Electrical circuit
7-2
Group 3 Component specification
7-11
Group 4 Connector destination
7-12
Group 5 Troubleshooting
7-14
SECTION 8 MAST
Group 1 Structure
8-1
Group 2 Operational checks and troubleshooting
8-5
Group 3 Adjustment
8-8
Group 4 Removal and installation
8-9
SECTION 6 HYDRAULIC SYSTEM
Group 1 Structure and function
6-1
Group 2 Operational checks and troubleshooting
6-15
Group 3 Disassembly and assembly
6-19
6-1
GROUP 1 STRUCTURE AND FUNCTION
SECTION 6 HYDRAULIC SYSTEM
1. HYDRAULIC CIRCUIT
D503HS01
1
Hydraulic gear pump
2
Flow regulator
3
Priority valve
4
Main control valve
5
Steering unit
6
Brake valve
7
Steering cylinder
8
Tilt cylinder
9
Lift cylinder
10
Suction filter
11
Return filter
12 Down control valve
13 Down safety valve
14 Hydraulic tank
6-2
D503HS02
WHEN THE LIFT CONTROL LEVER IS IN THE LIFT POSITION
1)
When the lift control lever is pulled back, the spool on the first block is moves to lift position.
The oil from hydraulic gear pump(1) flows into main control valve(4) and then goes to the large
chamber of lift cylinder(9) by pushing