Part of the Yanmar Repair Manuals.
When a 3TNV70 cranks slow and fires rough, the first honest answer comes from a compression gauge, and this Yanmar service manual tells you exactly how to take that reading and what to do with it. Publication M9961-02E070 covers the 2TNV70, 3TNV70, and 3TNV76 industrial diesels in 136 pages, whatever the engine happens to drive.
The core of the book is the full teardown: disassembly, inspection, and reassembly of the complete engine, with parts measurement, valve seat correction, and the service standards and bolt torque tables you check every clearance against. Around that sit maintenance schedules, troubleshooting charts, and chapters on the lubrication system, cooling system, fuel injection pump and governor, starter, alternator, and electric wiring.
An engine on a stand earns nothing, and neither does the machine waiting on it. Download the PDF, print the pages you need, and put real numbers under every measurement before it goes back together.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| Preface | 3 | Service Procedures for Tnv Series Engines, Standard Engine Specifications, Components, Work Equipment Service Manual, Engine Quality Improvement, Specification Changes |
| Safety Labels | 4 | Basic Safety Rules and Precautions, Safety Precautions, Inspection and Maintenance Procedures, Safety Consideration, Safety Marks and Their Meanings, Danger, Warning, Caution |
| Safety Precautions | 5-8 | Service Area, Work Wear, Tools, Genuine Parts and Materials, Fastener Torque, Electrical, Waste Management, Further Precautions |
| Precautions for Service Work | 9-11 | Precautions for Safety, Preparation for Service Work, Preparation Before Disassembly, Precautions in Disassembly, Precautions for Inspection, Measurement, Adjustment and Check |
| General | 16-29 | Engine Nomenclature, Specifications, Fuel Oil, Lubricating Oil and Cooling Water, Engine External Views, Structural Description |
| Inspection and Adjustment | 30-56 | Periodic Maintenance Schedule |
| Troubleshooting | 57-62 | Preparation Before Troubleshooting, Quick Reference Table for Troubleshooting, Troubleshooting by Measuring Compression Pressure |
| Disassembly, Inspection and Reassembly of Engines | 63-102 | Complete Disassembly and Reassembly (Introduction, Special Service Tools, Precautions Before and During Reassembly, Operation), Cylinder Head: Disassembly |
| Lubrication System | 103-105 | Lubrication System Diagram, Trochoid Pump Components, Disassembly, Servicing Points, Parts Inspection and Measurement (Trochoid Pump Inspection and Measurement) |
| Cooling System | 106-107 | Cooling Water System, Cooling Water Pump Components, Disassembly (Reverse the Below Procedure for Reassembly), Servicing Points |
| Fuel Injection Pump / Governor | 108-111 | Introduction |
| Starting Motor Specifications and Characteristics | 112-114 | Specifications and Characteristics, Structure of a Starting Motor and the Wiring Diagram, Performance |
| Alternator | 115-122 | 20A Alternator (Specifications, Structure, Wiring Diagram, Standard Output Characteristics, Inspection) |
| Electric Wiring | 123-127 | Electric Wiring Diagram (Alternator, Starter) |
| Service Standards | 128-133 | Engine Tuning, Engine Body, Lubricating Oil System (Trochoid Pump) |
| Tightening Torque for Bolts and Nuts | 134-135 | Tightening Torques for Main Bolts and Nuts, Tightening Torques for Standard Bolts and Nuts |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| All Models | ||
| Fuel injection nozzle pressure (Standard) | 11.8~12.8 MPa (120~130 kgf/cm²) | p. 48 |
| Fuel filter element replacement interval | Every 500 hours or 6 months | p. 43 |
| Fuel filter element Part No. | 119740-55650 | p. 43 |
| Air cleaner element cleaning/replacement interval | Every 250 hours or 3 months | p. 41 |
| Starter motor Manufacturer's model | P1.1 | p. 112 |
| Starter motor Yanmar code | 119717-77010 | p. 112 |
| Cooling water pump bearing inspection | Check for abnormal noise, sticking or play and water leakage. Replace whole pump assy if necessary. | p. 107 |
| Thermostat valve opening temperature | 69.5~72.5 °C | p. 55 |
| Thermostat full open lift (at 85°C) | 8 mm or more | p. 55 |
| 2TNV70 | ||
| Cooling water capacity (engine only) | 0.6 L | p. 128 |
| 2TNV70 Displacement | 0.570 L | p. 17 |
| 3TNV70 | ||
| 3TNV70 Displacement | 0.854 L | p. 18 |
