Part of the Yanmar Repair Manuals.
The injection pump is where a 2QM15 rebuild gets serious, and this Yanmar service manual (publication 2F015A, 221 pages, English) gives it a full chapter: pump construction, delivery valve checks, nozzle service against the 160 kg/cm2 plus or minus 10 pop pressure, filter and feed pump. From there it works through the whole engine: liner, piston, crankshaft and camshaft limits in Basic Engine, the governor, raw water cooling down to the Kingston cock and anticorrosion zinc, the reduction and reversing gear, and the 12 volt electrical system.
Every afternoon spent bleeding lines or chasing a soft compression stroke is time the engine sits dead in the boat. With the disassembly and reassembly chapter, its tool list, and the tightening torque table, you can take this engine down to a bare block on the stand and bring it back to factory clearances.
What's Inside This Yanmar 2QM15 Manual
| System | Pages | Key Topics |
|---|---|---|
| General | 4-20 | Exterior Views, Specifications, Principal Construction, Performance Curves, Sectional Views, System Diagrams, Standard Accessories |
| Basic Engine | 21-52 | Cylinder Block, Cylinder Liner, Cylinder Head, Piston, Connecting Rod, Crankshaft, Camshaft, Timing Gear |
| Fuel System | 53-69 | Injection Pump, Injection Nozzle, Fuel Filter, Fuel Feed Pump, Fuel Tank (Optional) |
| Governor | 70-78 | Injection Limiter, No-Load Maximum Speed Limiter, Engine Stop Spring |
| Intake and Exhaust System | 79-83 | Intake Silencer, Exhaust System, Breather Pipe |
| Lublication System | 84-91 | Lubrication System, Oil Pump, Oil Filter, Oil Pressure Regulator Valve, Oil Pressure Measurement |
| Cooling System | 92-102 | Water Pump, Thermostat, Anticorrosion Zinc, Kingston Cock, Bilge Strainer |
| Reduction and Reversing Gear | 103-124 | Installation, Operation and Maintenance, Inspection and Servicing, Disassembly, Reassembly |
| Remote Control System | 125-130 | Clutch Regulator One-Handle Remote Control, Decompression Remote Control, Engine Stop Remote Control |
| Electrical System | 131-155 | Composition, Battery, Starter Motor, Alternator, Alarm Circuit |
| Installation and Fitting | 156-171 | Propeller Selection, Engine Installation, Stern Equipment, Interior Piping and Wiring, Front Power Take-Off |
| Operating Instructions | 172-186 | Fuel Oil and Labricating Oil, Engine Operating Instructions, Troubleshooting and Repair |
| Disassembly and Reassembly | 187-214 | Disassembly and Reassembly Precautions, Disassembly and Reassembly Tools, Other, Disassembly, Reassembly, Tightening Torque |
| Inspection and Servicing | 215-220 | Periodic Inspection and Servicing |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Cylinder head tightening nut torque | 15 ~ 16 kg-m | p. 212 |
| Fuel sucked back (delivery valve) | 23.5mm³/stroke | p. 57 |
| Fuel filter element replacement period | Every 100 hours | p. 67 |
| Oil filter replacement period | Every 300 hours of engine operation | p. 89 |
| Secondary oil pressure standard value (Idling) | 0.5 kg/cm² (7.112 lb/in.²) | p. 91 |
| Secondary oil pressure standard value (3,000 rpm) | 2.5 ~ 3.5 kg/cm² (35.56 ~ 49.78 lb/in.²) | p. 91 |
| Compression Ratio | 23:1 | p. 6 |
| Fuel Injection Pressure | 160 ± 10 kg/cm² | p. 6 |
| Battery Voltage | 12 V | p. 144 |
| Alternator Output Current (Standard) | 35A/5000 rpm | p. 144 |
| Connecting Rod Bolt Tightening Torque | 4.5 ~ 5 kg-m | p. 212 |
