![Hitachi EX550 EX550-3 Repair Manual [Excavator]](https://youfixthis.com/wp-content/uploads/2014/12/2019-12-01_15-43-27-300x300.jpg)
Part of the Hitachi Repair Manuals.
Wrenching on a Hitachi EX400–EX450 series excavator? This 914-page Hitachi EX400–EX450 Series Service Manual PDF covers the EX400-3, EX400-3C, EX400LC-3, EX400LC-3C, EX400H-3, EX450H-3C, EX400LCH-3, and EX400LCH-3C hydraulic excavators. Inside: full electrical circuit diagrams with connector terminal positions, hydraulic schematics with circuit operation walkthroughs, a heavy troubleshooting section with harness checks, and step-by-step teardown procedures for the pump device, swing device, control valve, travel system, and front attachment. You also get operational performance test standards, so you can measure your machine against real factory numbers. Torque cap (84) to 340 N·m (253 lbf·ft), then fill the gearbox with 2.3 L of gear oil before it goes back to work. No more chasing wiring faults with a multimeter and a prayer. Bookmarked and text-searchable; jump straight to your model's circuit or find any spec by keyword.
What's Inside This Hitachi EX400–EX450 Series Manual
| System | Pages | Key Topics |
|---|---|---|
| Safety Procedures and Personal Protection | 1-8 | Safety Symbols, Emergency Preparedness, Protective Clothing, Noise Protection, Flying Debris Protection |
| Service Work Preparations | 9-20 | Machine Parking, Service Warnings, Machine Support, Travel System Maintenance, Swing System Maintenance |
| Maintenance Practices and Safety | 21-40 | Service Procedures, Work Area Cleanliness, Exhaust Fumes, Work Area Illumination, Battery Safety |
| Tool and Fluid Safety | 41-60 | Tool Usage, Moving Parts Safety, High-Pressure Fluids, Fire Prevention, Battery Handling |
| Welding, Lifting, and Disposal | 61-80 | Cooling System Service, Welding Safety, Heating Near Fluid Lines, Lifting Equipment, Fluid Disposal |
| Safety Signs and Machine Return | 81 | Safety Sign Maintenance, Machine Return Procedures, Handholds and Steps, Machine Operation Precautions |
| General Infomation | 9-20 | Precautions for Disassembling, Assembling, Tightening Torque, Torque Chart |
| Uppersturucture | 21-176 | Cab, Counterweight, Main Frame, Pump Device, Control Valve, Swing Device |
| Undercarriage | 177-292 | Swing Bearing, Travel Device, Center Joint, Track Adjuster, Front Idler, Roller |
| Front Attachment | 293-330 | Cylinder, Boom, Arm, Bucket |
| Special Tools | 331-338 | Special Tool List |
| Engine and Accessories | 339-522 | Engine Assembly, Lubricating System, Cooling System, Fuel System, Turbo Charger, Air Compressor |
| Specification | 531-562 | General Information, Fuels and Lubricants, Interchangeability, Machine Numbers, Component Specifications |
| Upperstructure | 563-626 | Outline, Tanks, Pump Device, Swing Device, Control Valve, Pilot Valve |
| Electrical System | 649-710 | Component Location, Control System, Monitor, Circuit Operation, Inspection and Maintenance |
| Hydraulic System | 711-736 | General, Control System, Circuit Operation |
| Operational Performance Test | 737-790 | Performance Test, Engine Test, Excavator Test, Hydraulic Component Test, Standard |
| Troubleshooting | 791-910 | Diagnosing Procedure, Connector, Troubleshooting a, Troubleshooting B, Troubleshooting C, Harness Check |
| Ex400-3 Electrical Circuit | 911 | Serial No. 5001 and Up (Issue 9601), Key Switch and Starter Circuit, Monitor Controller, Relays and Fusible Links, Pump and Control Valve Solenoids |
| Ex400-3 Electrical Circuit (Connector) | 912 | Serial No. 5001 and Up, Table of Connector Terminal Positions, Premated and Di-Cek Connectors, Wiper Relay Wiring |
| Ex400-3C Electrical Circuit | 913 | Serial No. 6001 and Up, Key Switch and Starter Circuit, Monitor Controller, Relays and Fusible Links, Pump and Control Valve Solenoids |
| Ex400-3C Electrical Circuti (Connector) | 914 | Connector Terminal Positions, Harness Circuit, Monitor Controller, Valve Controller, Alternator |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Torque for bolt (9) | 49 N·m (5 kgf·m, 36 lbf·ft) | p. 41 |
| Torque for bolt (7) | 49 N·m (5 kgf·m, 36 lbf·ft) | p. 41 |
| Bolt (2) torque | 9.8 N·m (7.2 lbf·ft) | p. 115 |
| Hose (3 to 8) torque | 39 N·m (29 lbf·ft) | p. 115 |
| Bolt (41) torque | 137 N·m (14 kgf·m, 101 lbf·ft) | p. 201 |
| Plug (42) torque | 69 N·m (7 kgf·m, 51 lbf·ft) | p. 201 |
| Tightening Torque Hose (1) to (4) | 205 N·m | p. 231 |
| Tightening Torque Hose (5) | 69 N·m | p. 231 |
| Fuel Filter Drain Plug Torque | 4.2 ± 0.8 kg·m (30.3 ± 5.8 lb.ft / 41.2 ± 7.9 N·m) | p. 364 |
| Fuel Filter Center Bolt Torque | 2.5 ± 0.5 kg·m (18.1 ± 3.6 lb.ft / 24.5 ± 4.9 N·m) | p. 364 |
| Full flow filter filtration | 10 μm | p. 561 |
| Full flow filter bypass cracking pressure | 147 kPa | p. 561 |
Hitachi EX400–EX450 Series Common Problems This Manual Covers
Hitachi EX400-3 boom, arm, and bucket slow or weak, all cylinders lose power under load
Check hydraulic oil level and condition before pulling anything apart. Test main pump delivery against the target flow rates on page 863: 183±10 cc/rev maximum in P mode, 48±10 cc/rev at neutral. If flow tests low, replace the 10 μm full flow filter element and inspect the pump regulator for wear.
Manual Section: Actuators Troubleshooting p. 863Machine pulls to one side during travel, one track slow or not turning
Swap the travel pilot lines side to side to isolate the fault. If the problem follows the circuit, pull the center joint apart. Clearance between body and spindle runs about 0.05 mm (0.004 in) per page 239. Replace parts if any ring sliding surface shows wear deeper than 0.5 mm (0.02 in).
Manual Section: Undercarriage p. 239Engine cranks but won't start, or starter turns engine over slowly when cold
Test the battery before chasing fuel problems; the machine runs a 170 Ah (20 hour rate) battery, listed on page 557. Verify charging output reaches 26 to 28 V with the engine running. If cranking speed is good, follow the hard-starting procedure starting to check fuel supply, injection pump, and valve clearance.
Manual Section: Engine Troubleshooting (Hard Starting)Hydraulic pump noisy and hot, oil temperature climbs, digging power drops off fast
Check the hydraulic tank level and look for foaming oil; air ingress and cavitation will destroy a pump quickly. Inspect the 177 μm (80 mesh) suction filter listed on page 561 for clogging, and tighten every suction line fitting. Replace the full flow filter element; its bypass cracks open at 147 kPa (21 psi), so a loaded element dumps unfiltered oil.
Manual Section: Specification p. 561Engine down on power, runs rough under load, black smoke from exhaust
Replace the fuel filter element; the spec is 5 μm filtration, shown on page 561. Drain water and sediment from the housing first. Torque the drain plug to 41.2 ± 7.9 N·m and the center bolt to 24.5 ± 4.9 N·m per page 364, then bleed air from the system before restarting.
Manual Section: Engine and Accessories p. 364Frequently Asked Questions
What is the torque specification for the track shoe bolts on an EX400-3?
The torque specification for the track shoe bolts on an EX400-3 is 1370 N·m (1010 lbf·ft). p. 13
How do I troubleshoot starting problems on a Hitachi EX450H-3C?
Troubleshooting starting problems involves checking the battery voltage, starter motor, and engine stop motor. If the starter does not rotate, check the battery voltage and connections; if it rotates but the engine does not start, check the fuel shut-off lever position and engine stop motor circuit as detailed on pages 850-852. p. 850
What is the standard valve clearance for the 6RB1 engine?
The standard valve clearance for both intake and exhaust valves on the 6RB1 engine is 0.60 mm (0.024 in) when cold. p. 345
What is the fuel tank capacity for the Hitachi EX400-3?
The fuel tank capacity for the Hitachi EX400-3 is 580 liters (153.2 US gal, 127.6 Imp gal). p. 543
What is the procedure for checking the main relief pressure on the EX400-3?
To check the main relief pressure, install a pressure gauge (ST 6934) into the pressure check port on the main pump delivery port. Ensure the hydraulic oil temperature is 50±5 °C (122±9 °F) and operate the control lever to full stroke to measure the pressure. p. 772
What exactly do I receive with this Hitachi EX400–EX450 Series Service Manual?
One searchable PDF covering 914 pages, delivered instantly. No disc, no shipping, no waiting on the post.
Does this Hitachi EX400–EX450 Series manual allow printing?
Yes. The PDF has no DRM restrictions, so print any page or section you need for your shop. Works with any standard printer.
Reviews
There are no reviews yet.