If your wheel loader carries a WA420-3 plate, this 946-page Komatsu WA420-3 shop manual PDF (factory number VEBM470104) was written for it, laid out in the original five sections from General through Maintenance Standard. Structure and Function fills roughly a third of the book, where hydraulic schematics trace the steering and work equipment circuits and wiring diagrams map transmission control, brakes and the air conditioner. Testing and Adjusting is built around standard value tables for engine, chassis and electrical parts, so you compare a reading against the factory number before any teardown begins on the transmission, clutch packs or parking brake. Check that the A/C low pressure switch cuts out at 2.0 bar, and torque 12 mm bolts to 112 ± 9.8 Nm. Nobody wants to split a transmission twice. Bookmarked and text-searchable, this copy is yours once bought, kept on the shop laptop for as long as your WA420-3 keeps loading trucks.
What's Inside This Komatsu WA420-3 Manual
| System | Pages | Key Topics |
|---|
| General | 9-30 | Dimensions and Weights, Specifications, Lubricating and Operating Means |
| Structure and Function | 31-328 | Power Train, Transmission Control, Steering System, Brake System, Air Conditioner |
| Testing and Adjusting | 329-618 | Standard Value Table for Engine, Standard Value Table for Chassis, Standard Value Table for Electrical Parts |
| Disassembly and Assembly | 619-894 | Transmission, Transmission Clutch Pack, Parking Brake |
| Maintenance Standard | 895-946 | Transmission, Transmission Control Valve, Brake |
Quick Reference Specifications
| Specification | Value | Page |
|---|
| Tread diameter 6mm torque | 13.2 ± 1.4 Nm | p. 30 |
| Tread diameter 8mm torque | 31.4 ± 2.9 Nm | p. 30 |
| Magnetic clutch switching capacity | 3.5 amps 13 VDC | p. 287 |
| Low pressure switch shut-off pressure | 2.0 bar | p. 287 |
| Turbocharger Torque Value | 45 Nm | p. 639 |
| Turbocharger Exhaust Clamp Torque Value | 8 Nm | p. 639 |
| Backlash between PTO drive gear and drive gear | 0.18 – 0.49 mm | p. 897 |
| Clearance between pump drive shaft and bearing | -0.039 – -0.011 mm | p. 899 |
| Side clearance (SAR(3)-100) | 0.13 – 0.18 mm | p. 929 |
| Clearance between inside diameter of plain bearing and outside of diameter of gear shaft (SAR(3)-100) | 0.06 – 0.149 mm | p. 929 |
| Side clearance (SAR(4)140) | 0.11 – 0.16 mm | p. 931 |
| Side clearance (SAR(1)28) | 0.10 – 0.15 mm | p. 931 |
