Part of the Yanmar Parts Manuals.
Halfway through a hose swap on a Yanmar B2U-1, the job stops the moment you need one exact part number and nobody at the counter can find it. That is what Yanmar's own parts catalog, publication Y00K3631, is for: every assembly on the B2U-1 crawler backhoe laid out in exploded diagrams with the genuine part number beside each callout.
The catalog runs 280 pages and covers 1998 machines from serial number 30501, fitted with the 3TNE74-N3AY and 3TNE74-EN3AY engines (engine serials from N00177 and N04808). Engine mounts, fuel system, radiator and oil cooler, hydraulic pump and piping, control valves, wiring diagrams, electrical parts, and undercarriage each get their own diagrams, plus paint part numbers for a correct-color restoration.
Download the PDF, find your assembly through the pictorial index, and print just the page you need, so the bench copy can get greasy while the file stays clean.
What's Inside This Parts Manual
| System | Pages | Key Topics |
|---|---|---|
| Preface | 1 | Parts Catalog History, Model Name, Yanmar Genuine Parts |
| Vehicle Painted Color | 2 | Painted Color, Main Parts, Under Traveling Body, Work Equipment, Canopy, Monitor |
| Paint Part No. | 3 | Painted Color, Munsell No., Color Division, Spray CAN |
| Wiring Diagram (1) | 4 | Starter, Alternator, Battery, Monitor, Fuel Sensor, Horn |
| Wiring Diagram (2) | 5 | Wiring Harness, Connector Routing, Fuse Box, Relay, Cab Harness, Ground Points |
| Picturesque Indx(1) | 6 | Engine Related Parts, Hyd. Oil System, Fuel Tank, Radiator, Oil Cooler, Electric Part |
| Picturesque Indx(2) | 7 | Operator Compartment, Control System, Canopy, Operator Seat, Floor Mat, Control Equipment |
| Picturesque Indx(3) | 8 | Under Carriage, Turning Related Parts, Travel, Swivel Joint, Track Roller, Track Frame |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Part: Spring Pin dimensions | 4mm x 8mm | p. 170 |
| Part: O-Ring 1A P-dimension | P-18.0 | p. 108 |
| Part: Shim thickness | 1.0mm | p. 170 |
| Part: Seal dimensions | 35mm x 45mm x 4mm | p. 174 |
| Part: Bulb wattage | 60W | p. 190 |
| Part: Circlip size | 52 | p. 228 |
| Part: O-Ring 1B P-dimension | P-11.0 | p. 248 |
