Part of the Yanmar Repair Manuals.
Put a pressure gauge on the main relief port and the spec you are testing against is right there: 24.5 MPa, with the adjustment procedure in the Pressure Adjustment section if the reading is off. That is what this book is for, the factory service manual for the Yanmar ViO50-6A crawler excavator and its 4TNV88-ZPBV diesel, publication MMB34ENMA00101, delivered as a 663-page PDF download.
Coverage runs from engine work (cylinder head, valve clearance, fuel injection pump, injectors, coolant pump) through the electrical system with wiring diagrams, an error code list, and monitor and alarm troubleshooting, to the hydraulics: control valve operation, swing motor, pressure adjustment, and removal and reinstallation of the pump, pilot valves, cabin, and air conditioner.
When the machine is down and there is nobody on the radio who knows it better than you, this is the book that gets it tracking and digging again.
What's Inside This Yanmar ViO50-6A Manual
| System | Pages | Key Topics |
|---|---|---|
| 2-5 Specifications for Attachment | 15 | - |
| 2-6 Periodic Inspection and Servicing | 15 | - |
| 2-7 Fuel, Lube Oil and Grease Recommended | 15 | - |
| 2-8 Hydraulic Circuit Schematic | 15 | - |
| 2-9 Wiring Diagram | 16-39 | Nominal and Allowable Values, Test and Adjustment Specifications, Rubber Crawler Specifications, Steel Crawler Specifications, Common Specifications of Steel & Rubber Crawlers |
| 3-8 Pressure Adjustment | 40-72 | Relief Valves, Swing Brake Valve, Cut-Off Valve, Safety Statements, Safety Precautions, Before You Begin Servicing, Introduction, Special Service Tools |
| 4-6 Starter Motor | 73 | |
| 4-7 Alternator | 73 | |
| 4-8 Electronic Control System | 73 | Before You Begin Servicing |
| 4-9 Electric Wiring | 73 | Electric Wiring Precautions |
| 4-10 Failure Diagnosis | 73 | Special Service Tools, Troubleshooting by Measuring Compression Pressure |
| 4-11 Troubleshooting | 74-244 | Quick Reference Table for Troubleshooting, Parts Layout of Electrical Equipment, LCD Monitor and Alarm Systems, Engine ECU, Circuit Description of Auto Deceleration Mode |
| 5-4 Error Code List | 245-252 | Control Valve Operation, Additional Operation of Control Valve, Boom, Arm, Bucket, Swing, Boom Swing, Blade |
| 6-6 Swing Motor | 253 | - |
| 6-8 Proportional Solenoid Valve for P.T.O | 254-489 | 6-1-1 Control Valve Operation, 6-1-2 Additional Operation of Control Valve, 6-2-1 Boom, 6-2-2 Arm |
| 7-7 Cabin | 489 | Removal and Reinstallation of Cabin, Disassembly and Reassembly of Cabin |
| 7-8 Air Conditioner | 490 | 7-1-1 Removal and Reinstallation of Engine, 7-1-2 Removal and Reinstallation of Starter Motor, 7-1-3 Removal and Reinstallation of Radiator and Oil Cooler |
| 7-5 Hydraulic Equipment | 489 |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Sprocket mounting bolt (M14) tightening torque | 127 to 149 N·m | p. 60 |
| Idler seal cover mounting bolt (M12) tightening torque | 79 to 93 N·m | p. 60 |
| Boom fulcrum pin lock plate (M14 x 35) tightening torque | 127 to 149 N·m | p. 62 |
| Arm fulcrum pin lock plate (M14 x 25) tightening torque | 127 to 149 N·m | p. 62 |
| Engine Oil Capacity | 7.4 L | p. 33 |
| Hydraulic Oil Tank Capacity | 38.0 L | p. 33 |
| Fuel Tank Capacity | 66.0 L | p. 33 |
| Rated Output / Engine Speed (GROSS) | 29.6/2400 kW/rpm | p. 22 |
| Maximum Torque / Engine Speed | 131.4 to 143/1440 N•m/rpm | p. 23 |
| System Relief Set Pressure (P1, P2) | 24.5 MPa | p. 19 |
| Swing Brake Valve Set Pressure | 21.6 MPa | p. 71 |
| Cylinder Head Bolt Tightening Torque | 85.3 to 91.1 N•m | p. 64 |
Yanmar ViO50-6A Common Problems This Manual Covers
Weak or slow boom and arm
When cycle times fall off and the bucket loses digging force, main relief pressure is the first thing to test. The Pressure Adjustment section gives procedures for the relief valves, swing brake valve, and cut-off valve, with the 24.5 MPa system set pressure to check against.
Manual Section: 3-8 Pressure Adjustment p. 40Alarm on the LCD monitor
A warning on the monitor with a crew standing around is no time to guess. The Troubleshooting chapter covers the LCD monitor and alarm systems, the engine ECU, and a quick reference table that maps symptoms to causes, plus a parts layout of the electrical equipment.
Manual Section: 4-11 Troubleshooting p. 74Engine clicks but will not crank
A dead crank on a cold morning usually comes down to the starter circuit. The Starter Motor section includes specifications, a troubleshooting procedure, and a component breakdown so you can bench-test before buying parts.
Manual Section: 4-6 Starter Motor p. 73Hard starting and rough running
Water and dirt in the fuel end up in the injection pump and injectors, and they show up as hard starts and uneven power. The fuel system chapter covers the injection pump, injectors, and checking and adjusting injection timing.
Manual Section: 4-3-7 Fuel Injection Pump p. 147Loose or worn undercarriage hardware
Track rollers, idlers, and sprockets take a constant beating, and bolts that back off chew up mating surfaces fast. The machine tightening torque tables list exact figures, including 198 to 230 N·m for track roller bolts, along with the thread locker to apply.
Manual Section: 3-7-1 Machine p. 59Bucket drifts down under load
A bucket that will not hold position points to cylinder seals or leakage across the control valve. The hydraulic control chapter explains control valve operation for the boom, arm, and other circuits so you can trace where the oil is going before pulling anything apart.
Manual Section: 6-8 Proportional Solenoid Valve for P.T.O p. 254Frequently Asked Questions
Which machine and engine does this manual cover?
The Yanmar ViO50-6A crawler excavator fitted with the 4TNV88-ZPBV diesel engine. It is the English-language factory service manual, Yanmar publication MMB34ENMA00101, 663 pages.
Does it include wiring diagrams?
Yes. The Wiring Diagram section covers the machine's electrical circuits, and the Troubleshooting chapter adds a parts layout of the electrical equipment so you can locate components before you start probing. p. 16
Are error codes explained?
Yes. There is a dedicated Error Code List section, and the Troubleshooting chapter covers the LCD monitor and alarm systems and the engine ECU for chasing the faults the codes point to. p. 245
Does it give torque specs for the undercarriage?
Yes. The machine tightening torque tables list figures such as 198 to 230 N·m for track roller bolts and 127 to 149 N·m for sprocket bolts, along with the recommended thread lockers. p. 59
What format is this manual in?
This is a 663-page searchable PDF ready for immediate download. Works on any device, so pull it up on your phone while you're under the hood. No shipping, no waiting.
Can I print specific sections of this Service Manual?
Yes, print as many copies as you want, and there are no restrictions. Many mechanics print the section they need and bring it to the shop floor.
Can I find wiring schematics in this Yanmar ViO50-6A manual?
Yes, full electrical schematics are included with wire colors, connector locations, and circuit descriptions.
Reviews
There are no reviews yet.