Part of the Hitachi Repair Manuals.
Wrenching on your Hitachi ZX40U-3? This 375-page Technical Manual (OEM #T1NG-E-00) covers the ZX 40U-3, 40U-3F, 50U-3, and 50U-3F hydraulic excavators, with sister models ZX27U-3, 30U-3, and 35U-3 sharing the same core systems. You get factory wiring diagrams for every key-switch circuit, hydraulic schematics tracing the pilot and main circuits, and a full troubleshooting section organized by error code, symptom, and monitor fault. Performance test standards pin down travel speed, swing drift, cylinder cycle times, and pump P-Q curves. Set the main relief valve to 24.5 MPa (3,550 PSI) and pilot pressure to 4.1 MPa; those numbers come straight from Hitachi, not a forum thread. No more chasing electrical gremlins with a test light and a hunch. The PDF is bookmarked with a live text layer: search any spec, jump to any circuit, get back in the seat.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| Introduction | 3-4 | To the Reader, Additional References, Manual Composition, Page Number |
| Safety | 5-36 | Recognize Safety Information, Understand Signal Words, Follow Safety Instructions, Prepare for Emergencies, Wear Protective Clothing, Protect Against Noise, Inspect Machine |
| General | 39-64 | Specifications, Working Ranges, Component Layout, Engine, Hydraulic Component, Electrical Component |
| System | 65-118 | Control System, Engine Control, Pump Control, Hydraulic System, Pilot Circuit, Electrical System |
| Component Operation | 119-212 | Pump Device, Revolution Sensing Valve, Swing Device, Control Valve, Pilot Valve, Travel Device |
| Operational Performance Test | 213-270 | Engine Test, Excavator Test, Component Test, Governor Adjustment |
| Troubleshooting | 271-375 | Diagnosing Procedure, Troubleshooting a, Troubleshooting B, Troubleshooting C, Electrical System Inspection |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Main Relief Set-Pressure | 24.5 MPa (250 kgf/cm2, 3550 psi) | p. 58 |
| Relief Set Pressure | 4.1 ± 0.2 MPa (42 ± 2 kgf/cm2, 595 ± 29 psi) | p. 60 |
| Thermostat Cracking temp. | 71 °C (160 °F) | p. 53 |
| Thermostat Full open temp. | 85 °C (185 °F) | p. 53 |
| Back pressure valve constant pressure | 0.3 MPa (3.06 kgf/cm², 43.5 psi) | p. 203 |
| Main Relief Valve Set Pressure (Main Pumps P1) | 25.3 ± 1.0 MPa (258 ± 10 kgf/cm², 3670 ± 145 psi) | p. 219 |
| Pilot relief valve tightening torque | 15 to 20 N·m | p. 249 |
| Swing relief valve tightening torque | 15.7 ± 0.1 N·m | p. 253 |
| Swing motor drain hose connection torque | 39 N·m (4 kgf·m, 29 lbf·ft) | p. 256 |
| Travel motor drain hose connection torque | 44 N·m (4.5 kgf·m, 32.5 lbf·ft) | p. 258 |
| Operating Weight (Canopy) | 4570 kg | p. 41 |
| Operating Weight (Cab) | 4730 kg | p. 41 |
