WORKSHOP MANUAL SECTION 1 GENERAL INFORMATION SECTION 3 BASE MACHINE (TRAVEL SYSTEM) Group 1 Precautions for DisassemGroup 1 Tire bling and Assembling Group 2 Drive Unit Group 2 Tightening Torque Group 3 Axle Group 3 Painting Group 4 Propeller Shaft Group 4 Bleeding Air from HydrauGroup 5 Brake Valve lic Oil Tank SECTION 2 BASE MACHINE (UPPER Group 6 Charging Block STRUCTURE) Group 7 Steering Pilot Valve Group 8 Steering Valve Group 1 Cab Group 9 Steering Cylinder Group 2 Counterweight SECTION 4 FRONT ATTAC
SECTION 1 GENERAL ―CONTENTS― Group 1 Specifications Group 3 Component Specifications Specifications ...........................................T1-1-1 Engine......................................................T1-3-1 Engine Accessories ..................................T1-3-6 Group 2 Component Layout Main Component Layout...........................T1-2-1 Electrical Component Layout ....................T1-2-4 Hydraulic Component ...............................T1-3-8 Electrical Component ...............
GENERAL / Component Layout MAIN COMPONENT LAYOUT (TRAVEL SYSTEM) 1 2 3 4 5 6 9 8 7 T4GB-01-02-004 1 - Front Axle 2 - Propeller Shaft (Front) 3 - Steering Cylinder 45- Pump Device Transmission 67- T1-2-3 Rear Axle Propeller Shaft (Rear) 89- Steering Accumulator Brake Pressure Sensor
GENERAL / Component Layout ELECTRIC COMPONENT LAYOUT (OVERVIEW) 14 Cab (Refer to T1-2-5) 2 1 13 12 Engine and Fan Pump (Refer to T1-2-10) 11 3 4 5 6 8 Pump Device (Refer to T1-2-11) Drive Unit (Refer to T1-2-11) 10 7 9 T4GB-01-02-019 1 - Hydraulic Oil Level Switch 5- Battery 9- 2 - Air Filter Restriction Switch 6- Boost Pressure Sensor 3 - ECM 7- Fuel Level Sensor 4 - Reverse Buzzer 8- Hydraulic Oil Temperature Sensor Emergency Steering Pump Delivery Pressure Switch 10 - Lift Ar
GENERAL / Component Layout PUMP DEVICE 1 2 3 6 5 T4GB-01-02-009 4 DRIVE UNIT 7 21 8 9 13 14 15 16 17 18 20 12 19 11 10 T4GC-01-02-001 1 - Main Pump 7- 2 - Regulator Torque Converter Input Speed Sensor 8 - Air Breather 3 - Priority Valve 9- 4 - Pump Delivery Pressure Sensor 5 - Pilot Pump 10 - Vehicle Speed Sensor 11 - Transmission Output Speed Sensor Charge Pump 12 - Transmission Middle Shaft Sensor 13 - Forward Clutch Solenoid Valve 14 - Reverse Clutch Solenoid Valve 15 - 1st Clut
GENERAL / Component Specifications ENGINE ZW220 Manufacturer ............................................ ISUZU Model........................................................ 6HK1XYWT-01 Type.......................................................... Diesel, 4 Cycle, Water Cooled, Over Head Valve, Inline, Direct Injection, Turbo Charged Cyl. NO. - Bore×Stroke............................. 6-115 mm×125 mm (4.53 in×4.92 in) 3 3 Piston Displacement.................................
GENERAL / Component Specifications ZW220 Engine Performance Curve (6HK1XYWT-01) Test Condition: 1. In conformity with JIS D1005 (Performance Test Method for Diesel Engine Used for Construction Machinery) under standard atmospheric pressure. 2. Equipped with the fan and alternator.
GENERAL / Component Specifications ZW250 Engine Performance Curve (6HK1XYWT-02) Test Condition: 1. In conformity with JIS D1005 (Performance Test Method for Diesel Engine Used for Construction Machinery) under standard atmospheric pressure. 2. Equipped with the fan and alternator.
SYSTEM / Control System Sensors and switches to detect signals for various operation controls and their controllers are as shown below.
SYSTEM / Control System Engine Control System Layout Work Mode Selector Switch L Accelerator Pedal Hydraulic Oil Temperature Sensor Accelerator Pedal Sensor N P Main Pump Delivery Pressure Sensor Shift Switch MC ECM Transmission Engine Torque Converter Output Speed Sensor Torque Converter Input Speed Sensor Monitor Unit Engine Coolant Temperature Sensor T2-1-7 T4GC-02-01-002
SYSTEM / Control System Engine Torque Control Purpose: Improving fuel consumption rate by changing the torque curve in response to input signals from the work mode selector switch, shift switch, and vehicle speed sensor Engine Torque 1 2 Operation: 3 1. When the signal of the selected work mode is transmitted to the MC, it detects signals from the main pump delivery pressure switch, shift switch, torque converter input speed sensor, and torque converter output speed sensor. 2.
SYSTEM / Control System Engine Torque Control Purpose: Improving fuel consumption rate by changing the torque curve in response to input signals from the work mode selector switch, shift switch, and vehicle speed sensor Engine Torque 1 2 Operation: 3 1. When the signal of the selected work mode is transmitted to the MC, it detects signals from the main pump delivery pressure sensor, shift switch, torque converter input speed sensor, and torque converter output speed sensor. 2.
SYSTEM / Control System Work Mode Selector Switch L＆C N P Main Pump Delivery Pressure Sensor Shift Switch MC ECM Transmission Engine Torque Converter Output Speed Sensor Torque Converter Input Speed Sensor Monitor Unit T4GC-02-01-005 NOTE: Illustration shows flow of the signal in case the light mode of the work mode selector switch and Speed 1 of the speed shift switch have been selected.
SYSTEM / Control System PUMP CONTROL Following pump controls are made.
SYSTEM / Control System Torque Reduction Control Purpose: Effectively utilizing engine horsepower by changing pump flow in response to increase or decrease of the engine speed due to traveling load Operation: 1. When accelerator pedal is stepped, MC makes arithmetic operation of the target engine speed. Q Flow 2.
SYSTEM / Control System Accelerator Pedal Accelerator Pedal Switch Main Pump Delivery Pressure Sensor MC ECM Engine Transmission Main Pump Regulator Pump Torque Control Solenoid Valve Torque Converter Output Speed Sensor Monitor Unit Torque Converter Input Speed Sensor T4GC-02-01-008 T2-1-19
SYSTEM/Hydraulic System Service Brake Brake Valve Front Brake Service Brake Accumulators Brake Valve Rear Brake Check Valves Relief Valve B Priority Valve A Spring Charging Block Pilot Pump NOTE: Illustration shows oil flow when the priority valve is closed in response to pressure decrease in the service brake circuit.
SYSTEM/Hydraulic System Bucket Pilot Valve Lift Arm Pilot Valve Spare Pilot Valve (Optional) Pilot Shutoff Valve To Service Brake Circuit Service Brake Accumulators Priority Valve Relief Valve B Pilot Pump Pilot Relief Valve Hydraulic Oil Tank PS1 PS2 X A Spring Pump Torque Control Solenoid Valve BR3 Parking Brake Pressure Sensor Parking Brake Solenoid Valve PP Charging Block NOTE: Illustration shows the oil flow in neutral condition of the pilot valve when the service brake accumulators are pre
SYSTEM/Hydraulic System Bucket Pilot Valve 1 2 Lift Arm Pilot Valve 3 4 Spare Pilot Valve (Optional) 5 6 7 8 Control Valve Pilot Shutoff Valve 8 Spare 2 7 To Service Brake Circuit Service Brake Accumulators 6 Priority Valve 2 Spare 1 5 Bucket 1 Pilot Pump 4 Slow-Return Valves Lift Arm 3 Main Pump PP T4GB-02-02-002 Charging Block NOTE: Numeral of each port of the pilot valves and the control valve shows the port to be connected.
SYSTEM/Hydraulic System Bucket Pilot Valve 1 2 Lift Arm Pilot Valve 3 4 Spare Pilot Valve (Optional) 5 6 7 8 Control Valve Pilot Shutoff Valve 8 Spare 2 7 To Service Brake Circuit Service Brake Accumulators 6 Priority Valve 2 Spare 1 5 Bucket 1 Pilot Pump 4 Slow-Return Valves Lift Arm 3 Main Pump PP Charging Block T4GB-02-02-021 NOTE: Numeral of each port of the pilot valves and the control valve shows the port to be connected.
SYSTEM/Hydraulic System Charging Block Pilot Pump Pump Torque Control Solenoid Valve Hydraulic Oil Tank PS2 Command Signal from MC Pilot Presser (X) Pump From Control Valve Orifice Control Valve Pi2 Pi1 Main Pump Servo Piston Main Pump Regulator T4GB-02-02-003 NOTE: Control valve illustrated is for ZW220.
SYSTEM/Hydraulic System Service Brake Brake Pedal Front Brake Service Brake Accumulators Brake Valve Rear Brake Check Valves Relief Valve Priority Valve Spring Parking Brake Pressure Sensor Parking Brake Solenoid Valve Parking Brake Release Pilot Accumulator No Signal for Parking Brake Release Brake Charging Block Pilot Pump NOTE: Illustration shows oil flow when the relief valve and the priority valve are open in response to pressure increase in the service brake circuit, and also oil flow when
SYSTEM/Electric System Key Switch From #163Terminal of Fuse Box A From #6 terminal of Fuse Box B 684 Monitor Unit 119 From Terminal L of Alternator NEUTRAL Parking Brake Switch イ Parking Brake Parking Brake Relay 2 Relay 1 OFF AB E F GH A B CD E A B CD E 684 Monitor Unit 119 To #638 Terminal of Fuse Box B Fuse (100A) 157 123 54 55 163 693 108 12 144 133 121 696 695 698 699 700 (When forming a self-exciting circuit) ON Fuse Box A 264 362 692 210 124 135 Battery Relay 79 99 120 694 697
COMPONENT OPERATION / Pump Device OUTLINE Pump device has a main pump (1) and a pilot pump (2), and main pump (1) has a built-in priority valve (6). Driving force of the engine is transmitted to the shaft (3) through the transmission input shaft, and actuates main pump (1) and pilot pump (2). Main pump (1) is a swash-plate type variable displacement axial plunger pump. Pilot pump (2) is a gear pump. Pump delivery pressure sensor (4) is provided for controlling the main pump.
COMPONENT OPERATION / Pump Device Pump Control Pressure Pi1 Pilot To Hydraulic Primary Oil Tank Pressure Pg 3 2 4 1 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 13 Self Delivery Pressure Pd1 12 11 10 T4GB-03-01-008 Pump Control Pressure Pi1 To Hydraulic Oil Tank Pilot Primary Pressure Pg 3 2 4 1 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 13 Self Delivery Pressure Pd1 12 10 11 T4GB-03-01-009 T3-1-9
COMPONENT OPERATION / Pump Device Pump Control Pressure Pi1 To Hydraulic Oil Tank Pilot Primary Pressure Pg 3 2 4 1 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 13 Self Delivery Pressure Pd1 12 10 11 T4GB-03-01-010 Pump Control Pressure Pi1 To Hydraulic Oil Tank Pilot Primary Pressure Pg 3 2 4 1 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 13 Self Delivery Pressure Pd1 12 10 11 T4GB-03-01-011 T3-1-11
COMPONENT OPERATION / Pump Device Pump Control Pressure Pi1 5 To Hydraulic Oil Tank Pilot Primary Pressure Pg 6 7 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 8 9 13 Self Delivery Pressure Pd1 12 10 11 T4GB-03-01-012 5 Pump Control Pressure Pi1 To Hydraulic Oil Tank Pilot Primary Pressure Pg 6 7 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 8 13 Self Delivery Pressure Pd1 9 12 10 11 T4GB-03-01-013 T3-1-13
COMPONENT OPERATION / Pump Device 5 Pump Control Pressure Pi1 To Hydraulic Oil Tank Pilot Primary Pressure Pg 6 7 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 8 13 Self Delivery Pressure Pd1 9 12 10 11 T4GB-03-01-014 5 Pump Control Pressure Pi1 To Hydraulic Oil Tank Pilot Primary Pressure Pg 6 7 Pump Control Pressure Pi2 Pump Torque Control Pressure ST Self Delivery Pressure Pd1 13 12 10 11 T4GB-03-01-015 T3-1-15
COMPONENT OPERATION / Pump Device 5 Pump Control Pressure Pi1 To Hydraulic Oil Tank Pilot Primary Pressure Pg 6 7 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 8 9 13 Self Delivery Pressure Pd1 12 10 11 T4GB-03-01-016 5 Pump Control Pressure Pi1 To Hydraulic Oil Tank Pilot Primary Pressure Pg 6 7 Pump Control Pressure Pi2 Pump Torque Control Pressure ST 8 13 Self Delivery Pressure Pd1 9 12 10 11 T4GB-03-01-017 T3-1-17
COMPONENT OPERATION / Pump Device PILOT PUMP Drive gear (1) is driven throught the shaft of the main pump, and the diven gear (2) geared to this also rotates. 1 - Drive Gear Suction Port 1 2 2 - Driven Gear Delivery Port T137-02-03-005 PUMP DELIVERY PRESSURE SENSOR Pump delivery pressure necessary for various kinds of control is sensed. Hydraulic pressure is received by the diaphragm (9), and deformation of the diaphragm is sensed as an electric signal.
COMPONENT OPERATION / Control Valve Bucket Cylinder Lift Arm Cylinder Control Valve Overload Relief Valve Bucket Lift Arm Parallel Circuit Main Relief Valve Main Pump T4GB-03-02-023 T3-2-17
COMPONENT OPERATION / Hydraulic Fan Motor REVERSE CONTROL VALVE Fan motor is reversed by operations of the reverse control solenoid valve and the reverse spool. Operation • At Neutral of Reverse Control Solenoid Valve 1. When reverse control solenoid valve (1) is at neutral, the pressure oil (P) from the fan pump is blocked by changeover valve (2). 2. As reverse spool (3) is being pushed by spring (4), the pressure oil (P) from the fan pump flows to port MB, and the fan motor rotates normally.
COMPONENT OPERATION / Steering Pilot Valve OPERATION 4 Sleeve (3), spool (4), and drive (7) are mutually connected by pin (5). When the handle (or the spool (4)) is turned, a relative angular difference arises between sleeve (3) and spool (4) because the hole of spool (4) is a lengthened one. Movement of the steering handle is conveyed only to spool (4), and port P (from the steering pump) is connected to port R (to the steering valve) or port L through sleeve (3) and spool (4).
COMPONENT OPERATION / Pilot Valve Pusher Stroke: between A and B 1 2 3 4 5 6 Port T (Clearance of Part A: 0) （A） Port P Notch Part 7 Output Port 1 - Lever 2 - Push Rod 3 - Pusher 4 - Spring Guide T4GB-03-05-004 T4GB-03-05-003 5 - Balance Spring 6 - Return Spring T3-6-3 7- Spool
COMPONENT OPERATION / Pilot Valve Pusher Stroke: between C and D Pusher Stroke: between E and F 3 5 (C) Port T 4 Notch Part Face B Port P Port P 7 7 Output Port 3- Pusher 4- Spring Guide Output Port T4GB-03-05-005 5- T3-6-5 Balance Spring 7- Spool T4GB-03-05-006
COMPONENT OPERATION / Pilot Valve Electromagnetic Detent Coil for detent is installed at the push rod part of the pilot valve. 3. Adsorbed condition is retained until the coil assembly is unexcited or until adsorption is forcefully cancelled by moving the control lever the other way around. 1. When one of the control levers is tilted, push rod (2) and plate (8) of the other are pushed upwards by the spring force. 2.
COMPONENT OPERATION / Drive Unit Side View of Transmission 3 2 1 4 5 3 6 7 10 8 9 11 T4GC-03-09-005 1 - Converter Inlet Pressure Port 2 - Regulator Valve 3 - Regulator Pressure Port 4- Forward Clutch Pressure Port 5 - Reverse Clutch Pressure Port 6 - 1st Speed Clutch Pressure Port 7- 2nd Speed Clutch Pressure Port 8 - 3rd Speed Clutch Pressure Port 9 - 4th Speed Clutch Pressure Port T3-9-7 10 - Parking Brake Release Pressure Inlet 11 - Parking Brake Pressure Switch Port
COMPONENT OPERATION / Drive Unit Forward 3rd Speed Furthermore, torque is outputted from 3rd hub gear (13) to high-range gear (14), and eventually outputted to output gear (15). In the case of forward 3rd speed, the forward clutch and the speed 3 part of the 3rd & 4th Speeds clutch are connected. Torque converter transmits torque to F hub gear (4) geared to the input gear (1). Torque from F hub gear (4) is transmitted to 3rd Speed hub gear (13) through F - R gear (3) and idler gear (8).
COMPONENT OPERATION / Axle Traveling Straight with the Same Road Resistances to Left and Right Tires As the differential pinion gear and the left and right pinion gears rotate solidly, the drive forces of the left and right tires are the same similarly to the TPD. Traveling on Soft Roads (Different Road Resistances to Left and Right Tires) Drive force is transmitted to the case, pressure ring, and spider through the ring gear.
COMPONENT OPERATION / Brake Valve 1 5 7 From Port M1 of Charging Block M1 From Port M2 of Charging Block M2 BR1 BR2 T To Front Service Brake To Rear Service Brake 8 9 T4GB-03-11-003 T3-11-3
