Part of the Doosan Repair Manuals.
Working on a DX420LC? This 900-page Doosan Daewoo DX420LC Shop Manual PDF (OEM #K1009096E) walks you through every system on the track excavator, from the swing bearing to the KVMG-400-DA control valve. Inside: a full electrical schematic set, hydraulic schematics with complete circuit routing, and a dedicated troubleshooting, testing and adjustment section covering pilot pressure and the power mode valve. You also get teardown procedures for the main pump, swing motor, travel motors, and all three cylinders. Torque the fuel filter head plug to 27 kg-m (200 ft lb) and fill the 550-liter fuel tank knowing your numbers came straight from Doosan. No more chasing hydraulic faults with a pressure gauge and a hunch. Bookmarked with a full text layer; type a spec, jump to the section, get back on the sticks.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| Safety Precautions | 4 | Track Excavator Safety |
| Safety | 5-52 | Applicable Models, To the Operator of a Doosan Daewoo Excavator, General Safety Essentials, Location of Safety Labels, Summary of Safety Precautions for Lifting in Digging Mode |
| Specifications | 53-82 | Specification for DX420LC |
| General Maintenance Procedures | 83-102 | Applicable Models, Welding Precautions and Guidelines, Hydraulic System - General Precautions, Maintenance Service and Repair Procedure, Hydraulic System Cleanliness and Oil Leaks |
| Standard Torques | 103-118 | Applicable Models, Torque Values for Standard Metric Fasteners, Torque Values for Standard U.S. Fasteners, Type 8 Phosphate Coated Hardware, Torque Values for Hose Clamps |
| Upper Structure | 119-218 | Cabin, Counterweight, Fuel Tank, Swing Bearing, Swing Reduction Gear |
| Lower Structure and Chassis | 219-298 | Track Assembly, Air Conditioner SP000025 |
| Engine and Drive Train | 299-308 | Drive Coupling (Main Pump) |
| Hydraulic System Troubleshooting, Testing and Adjustment | 309-348 | Hydraulic Schematic, Working Components, Pilot Pressure, Power Mode Valve, Boom/Front Priority Valve |
| Accumulator | 349-356 | Gas-Charged Storage, Precharge Pressure, Diaphragm, P1 Rated Pressure |
| Center Joint (Swivel) | 357-370 | Hydraulic Oil Flow, 360-Degree Rotation, Disassembly, Reassembly |
| Cylinders | 371-400 | Boom Cylinder, Arm Cylinder, Bucket Cylinder, Rod Stopper, Cushioning |
| Swing Motor | 401-436 | Rotary Power, Relief Valve, Parking Brake, Makeup Check Valve, Time Delay Valve |
| Travel Motor (with Gearbox) | 437-492 | Two-Stage Planetary Gearbox, Brake Valve, Capacity Control, Overload Valve |
| Main Pump | 493-550 | Pump Regulator, Rotary Groups, Auxiliary Drive, Control Module, Tightening Torques |
| Control Valve (Kvmg-400-Da) | 551-742 | Neutral Passage, Signal Passage, Anti-Drift Valve, Main Relief Valve, Overload Relief Valve |
| Electrical System | 743-870 | Electrical System SP000269, Electrical Schematic (DX420LC) |
| Attachments | 871-900 | Boom and Arm, Bucket |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Fuel tank capacity | 550 liters (145 U.S. gal) | p. 149 |
| Bolt torque for fuel filter head plug | 27 kg•m (200 ft lb) | p. 154 |
| Filter cleaning interval | 500 hours | p. 267 |
| Hydraulic reservoir return line and pilot circuit filter rating | 10 micron | p. 319 |
| Reservoir intake strainer micron rating | 177 micron | p. 319 |
| Braking Torque | 644 Nm | p. 443 |
| Brake Release Pressure | 15.7 kg/cm2 | p. 443 |
| Outer dia. of piston (d max - d min) | 0.01 mm | p. 459 |
| Inner dia. of cylinder bore (D max - D min) | 0.01 mm | p. 459 |
| Shaft wear depth for reusability | less than 0.05mm | p. 460 |
| Hydraulic System Capacity | 420 liters | p. 68 |
| Hydraulic Reservoir Capacity | 265 liters | p. 68 |
