Part of the Kubota Repair Manuals.
This is the Kubota Service Manual for the R420S, R520S, R420 Alpha, and R520 Alpha wheel loaders. It covers the D1503-M-T-E2RP-1 and V2203-M-E2RP diesel engines and runs 322 pages with a searchable text layer, including the KTC, KCL, and KTA versions plus the EU version machines.
Organized as a full service book, it moves through general identification and safety, the machine body and front attachment, the engine, the hydraulic system, the brake system and power train, and the electrical system. You get machine specifications, troubleshooting charts, testing procedures, pressure figures, and detailed servicing steps.
With the largest section devoted to hydraulics, this manual is built for the loaders where lift, tilt, and travel problems live. Use it to diagnose a fault, test a circuit, and rebuild a system correctly on your own R420 or R520 wheel loader.
Other edition of this manual
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| 1. General | 5-22 | [1] Body and Engine Identification Marks, [2] Safety Precautions for Servicing, Disassembly and Reassembly, [3] Important Safety Process and Critical Functional Process |
| 2. Machine Body & Front Attachment | 23-55 | Specifications (Machine Specifications, Main Specification: EU-version), Installing the Frame-Related Parts, Center Pin, Rear Frame |
| 3. Engine | 56-70 | [1] Specifications, [2] Engine Assy Dismounting, [3] Engine Accessories |
| 4. Hydraulic System | 71-234 | [1] Troubleshooting, [2] Specifications, [3] Testing, [4] Servicing |
| 5. Brake System and Power Train | 235-261 | [1] Brake System, [2] Power Train |
| 6. Electrical System | 262-322 | [1] Testing, [2] Troubleshooting, [3] Specifications, [4] Wire Harness Installation, [5] Specifications for Electric Components and Service |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| All Models | ||
| Fuel tank capacity | 54 L (14.3 U.S.gal.) | p. 23 |
| Hydraulic oil tank capacity | 42 L (11.1 U.S.gal.) | p. 23 |
| Hydraulic oil total system capacity | 60 L (15.9 US gal) | p. 12 |
| Wheel hub bolts tightening torque | 275 to 314 N-m (203 to 231 ft-lb) | p. 20 |
| M6 bolt tightening torque (S40C, S45C) | 9.8 ~ 11.3 N-m | p. 18 |
| Parking Valve Max. pressure | 4.9 MPa (711 psi) | p. 83 |
| R420S | ||
| Engine oil pan capacity, R420S | 7.0 L (1.8 US gal) | p. 12 |
| Front tire pressure, R420S | 0.26 ± 0.01 MPa (36.9 ± 1.4 psi) | p. 20 |
| R520S | ||
| Engine oil pan capacity, R520S | 9.5 L (2.5 US gal) | p. 12 |
| Front tire pressure, R520S | 0.22 ± 0.01 MPa (31.2 ± 1.4 psi) | p. 20 |
| R420Sα | ||
| LST Pump Operating pressure (at bench), R420Sα | 36.8 MPa (5334 psi) | p. 81 |
| R520Sα | ||
| LST Pump Operating pressure (at bench), R520Sα | 41.2 MPa (5974 psi) | p. 81 |
