Part of the Yanmar Repair Manuals.
Pull the end cover off the sea water pump on a 3JH2 and you can measure the impeller against the wear limits printed in this manual before deciding whether an overheating problem is the pump's fault at all. This is Yanmar's service manual for the 3JH2 series marine diesels, the 3JH2E, 3JH2-TE, 3JH25A and 3JH30A, three cylinder engines with an 82 x 86 mm bore and stroke and 1.303 L displacement. The KM3A, KM3P1, KM3P3 and KM35P1 reduction and reversing gears get their own construction, servicing, disassembly and reassembly coverage.
Across 308 pages it works through the basic engine parts, fuel injection pump and governor, turbocharger, lubrication, cooling, remote control and electrical systems, with service data, clearances and tightening torques for a full teardown. It is delivered as a PDF download you can print page by page, so the clearances and torque figures are on the bench when the engine goes back together.
Other edition of this manual
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| General | 6-28 | Exterior Views, Specifications, Engine Outline, Performance Curves, Piping Diagrams |
| Basic Engine Parts | 29-58 | Cylinder Block, Cylinder Head, Piston and Piston Pins, Connecting Rod, Crankshaft and Main Bearing, Camshaft and Tappets, Timing Gear, Flywheel and Housing |
| Fuel Injection Equipment | 59-98 | Fuel Injection Pump Service Data, Governor, Disassembly Reassembly and Inspection of Fuel Injection Pump, Fuel Injection Pump and Governor, Fuel Feed Pump, Fuel Injection Nozzle |
| Intake and Exhaust System | 99-117 | Turbocharger, Mixing Elbow |
| Lubrication System | 118-131 | Lube Oil Pump, Lube Oil Filter, Oil Pressure Control Valve, Lube Oil Cooler, Piston Cooling Nozzle, Rotary Waste Oil Pump(Optional) |
| Cooling Water System | 132-151 | Sea Water Pump, Fresh Water Pump, Heat Exchanger, Pressure Cap and Sub Tank, Thermostat, Kingston Cock(Optional), Sea Water Filter(Optional) |
| Reduction and Reversing Gear | 152-208 | Km3A (Construction, Shifting Device, Servicing, Disassembly, Reassembly), Km3P1, Km3P3, Km35P1 (Construction |
| Remoto Control | 209-215 | Remoto Control System, Remoto Control Installation, Remoto Control Inspection, Remote Control Adjustment |
| Electrical System | 216-271 | Electricai System, Battery, Starter Motor, Alternator, Instrument Panel, Warning Deices, Air Heater(Optional), Electric Type Engine Stop Device(Optional) |
| Disassembly and Reassembly | 272-307 | Disassembly and Reassembly Precautions, Disassembly and Reassembly Tools, Disassembly and Ressembly, Bolt/Nut Tightening Torque, Test Running |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Cylinder head bolt tightening torque (Partial) | 3.5 ~ 4.5 kg-m (25.3 ~ 32.5 ft-lb) | p. 295 |
| Cylinder head bolt tightening torque (Complete) | 7.5 ~ 8.5 kg-m (54.2 ~ 61.5 ft-lb) | p. 295 |
| Sea water pump impeller width (Standard) | 31.6 ~ 31.8 mm (1.2440 ~ 1.2519 in.) | p. 137 |
| Sea water pump wear plate thickness (Standard) | 2 mm (0.0787 in.) | p. 12 |
| Fuel filter filtering method | filter paper | p. 97 |
| Fuel filter filtering area | 840cm² (130.23in.²) | p. 97 |
| Alternator brush length (Maintenance standard) | 16 (0.6299) | p. 5 |
| Alternator brush length (Wear limit) | 9 (0.3543) | p. 12 |
| Lube oil filter filtration area | 800cm² (124in.²) | p. 127 |
| Lube oil filter discharge volume | 20 L/min (1220 in.³/min) | p. 127 |
| Number of cylinders | 3 | p. 10 |
| Bore x Stroke | 82 x 86 mm | p. 12 |
