Part of the Yanmar Repair Manuals.
Lay a strip of plastigage on a crank journal of a 4JH2 and you need one number before the cap goes back on: 0.038 to 0.093 mm oil clearance, with a 0.25 mm wear limit. That figure sits on page 54 of this Yanmar service manual, the factory reference for the 4JH2E, 4JH2-TE, 4JH2-HTE, 4JH2-DTE and 4JH2-UTE marine diesel engines.
Across 406 pages it works through the basic engine parts, the fuel injection pump and governor, the turbocharger, the lubrication and cooling water systems, the reduction and reversing gear, and the electrical system, with a full disassembly and reassembly chapter closing it out. Wear limits, clearances and tightening torques are tabulated where you measure them.
Guessing a bearing clearance or a torque figure costs you a second teardown, or a ruined crank. The PDF downloads instantly and carries 112 bookmarks, so the spec you need is a click away.
Complete the set for your 4JH2 Series
- Parts Catalog: Yanmar 4JH2 Series Parts Catalog (Marine Diesel Engine)
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| History of Revision | 3 | Injection Timing Changed, Tightening Torque of Bolts and Nuts for General Use, Tightening Torque of Nut for Remote Control Cable Connection of Clutch Shifting Lever |
| General | 6-32 | Exterior Views, Specifications, Performance Curves, Engine Cross Section, Dimensions, Piping Diagrams |
| Inspection and Servicing of Basic Engine Parts | 33-64 | Cylinder Block, Cylinder Liners, Cylinder Head, Piston and Piston Pins, Connecting Rod, Crankshaft and Main Bearing, Camshaft and Tappets, Timing Gear |
| Fuel Injection Equipment | 65-163 | 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 | 164-182 | Turbocharger, Mixing Elbow |
| Lubrication System | 183-195 | Lube Oil Pump, Lube Oil Filter, Oil Pressure Control Valve, Lube Oil Cooler, Piston Cooling Nozzle, Rotary Waste Oil Pump (Optional) |
| Cooling Water System | 196-214 | Sea Water Pump, Fresh Water Pump, Heat Exchanger, Pressure Cap and Sub Tank, Thermostat, Kingston Cock (Optional) |
| Reduction and Reversing Gear | 215-303 | Installation, Operation and Maintenance, Servicing, Disassembly, Reassembly, Special Tools, Shifting Device |
| Remote Control (Optional) | 304-310 | Remote Control System, Remote Control Installation, Remote Control Inspection, Remote Control Adjustment |
| Electrical System | 311-368 | Battery, Starter Motor, Alternator, Instrument Panel, Warning Devices, Air Heater (Optional) |
| Disassembly and Reassembly | 369-404 | Disassembly and Reassembly Precautions, Disassembly and Reassembly Tools, Bolt/Nut Tightening Torque, Test Running |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| Oil pressure control valve regulating pressure | 3.5 ~ 4.5 kg/cm² (49.78 ~ 64.00 lb/in.²) | p. 191 |
| Main bearing cap bolt tightening torque | 10.5 ~ 11.5 kg-m (75.92 ~ 83.16 ft-lb) | p. 55 |
| Main bearing oil clearance (Crank journal and bushing oil clearance) | Standard: 0.038 ~ 0.093 mm (0.0014 ~ 0.0036 in.), Wear limit: 0.25 mm (0.0098 in.) | p. 54 |
| Connecting rod bolt tightening torque | 5.0 ~ 5.5 kg-m (36.15 ~ 39.77 ft-lb) | p. 51 |
| Oil pressure alarm operating pressure | 0.1 ~ 0.3 kg/cm² (1.422 ~ 4.266 lb/in.²) | p. 350 |
| Fuel Injection Pump Injection Starting Pressure | 195 ~ 205 kg/cm² | p. 66 |
| Lube Oil Filter Discharge Volume | 30 L/min | p. 189 |
| Oil Pressure Regulating Pressure | 3.5 ~ 4.5 kg/cm² | p. 191 |
| Thermostat Opening Temperature | 75 ~ 78°C | p. 210 |
