1995–2002 Yanmar 3JH3/4JH3 Marine Diesel Engine Service & Repair Manual (P/N HINSHI-H8009)

Yanmar’s service manual covers the 1995–2002 3JH3 and 4JH3 marine diesel families: 3JH3E, 3JH3BE, and 3JH3CE, including their A variants, plus 4JH3E, 4JH3BE, 4JH3CE, and 4JH3CE1. Publication HINSHI-H8009, 2002.4 revision, addresses three- and four-cylinder engines.

Bookmarks, search, and wiring detail: Embedded bookmarks link to chapters and many subsections. Text search is limited to the opening cover; the manual pages are not searchable. Small labels in the B- and C-type wiring diagrams require zooming.

• Engine repair: Cylinder block and head inspection, valve service, rotating assembly measurements, and engine disassembly and reassembly with torque and wear-limit tables.

• Fuel injection: YPES-CL pump and governor service, nozzle testing, injection timing, fuel delivery calibration tables, and fuel feed pump test data.

• Cooling and lubrication: Sea water pump service, heat exchanger inspection, thermostat testing, and oil pump performance checks.

• Marine gears and controls: KM3A, KM35A, KM3P, and KM35P overhaul, plus remote control cable installation and adjustment.

• Electrical diagnosis: Starter motor overhaul, alternator testing, instrument panel checks, and fault-isolation charts for starting and charging systems.

• Installation references: Engine exterior views and dimensional drawings, piping diagrams, component cross sections, and exploded views showing assemblies and connections.

Written for engineers working in sales, service, inspection, and maintenance, this manual assumes basic mechanical knowledge.

Engine Construction and Inspection

Cylinder block and cylinder head repair data cover piston ring clearance, crankshaft journal wear limits, camshaft height, and timing gear backlash. Valve-seating inspection and guide replacement are included.

Engine removal, disassembly, and reassembly procedures extend through gear timing and final no-load and load checks. Intake and exhaust coverage addresses the intake silencer, manifolds, and L- and U-type mixing elbows.

Fuel System Calibration and Technical Data

Plunger and delivery-valve pressure tests accompany cylinder-to-cylinder fuel delivery checks. Pump-bench calibration references include rack indicator 158090-51500 and plunger gauge 121820-92540.

3JH3E pump versions: The instructions distinguish E/# A01157 and earlier from the EPA/ARB-certified engines at E/# A01158 and later, with different replacement-pump alignment and timing requirements. This distinction helps match pump service procedures to the engine’s build.

Nozzle service covers opening-pressure and spray checks. Holder-clamping precautions address damage to the high-pressure mounting threads.

Working around high-pressure marine diesel fuel systems requires proper shop safety precautions.

Cooling and Lubrication Service

Fresh water and sea water circuit diagrams and a heat exchanger cross section accompany pump, pressure-cap, and thermostat checks. Fresh water pump repair is limited to assembly replacement; sea water pump service includes impeller and seal work.

Lubrication coverage includes trochoid oil pump inspection, flow and pressure data, pressure-regulating valves, and the 4JH3 oil cooler.

Marine Gear Overhaul and Remote Controls

Reduction and reversing gear procedures cover drive-cone inspection and lapping, thrust collars, cup springs, and input/output shaft shimming, supported by sectional views.

KM35A and KM35P versions use larger output shafts and omit the KM3 torque limiter; KM35P also has a different drive cone. Remote control coverage addresses Morse MT3/MV units and 33C shift and speed cables.

SD31/SD40 sail drives appear in engine application data; internal sail-drive overhaul is outside this manual’s repair coverage.

Starter, Alternator, and Instrument Panel Diagnosis

Starter repair covers armature, brush, commutator, magnetic-switch, and pinion checks. Battery load tests cover voltage drop.

Alternator sections distinguish the standard 12V/55A unit from the optional 12V/80A unit, with rotor, stator, diode, and regulator tests.

B- and C-type wiring diagrams, charging-fault flowcharts, and instrument panel diagnostics cover circuit faults, tachometer signals, and pressure/temperature senders.

Alternator precautions explain how high-voltage insulation testers can damage the diodes and IC regulator.

English PDF and Included Revision Pages

The printable 305-page English PDF contains 296 pages across Chapters 0–11 plus nine pages of front and back matter: two front covers, a foreword, revision history, three emissions-information pages, an index, and the back cover. All revised and added technical pages are already included in that total.