This is the service manual for the Mitsubishi S4K and S6K diesel engines, including the turbocharged S4K-T and S6K-T, publication 99499-10190 in English. These four and six cylinder engines are widely used in excavators and other heavy equipment, and this 148 page book is written for workshop level repair rather than routine operation.
Mechanics can use it to work through testing and adjusting, valve clearance and injection timing, accessory removal, and full engine teardown covering cylinder heads, timing gears, camshaft, pistons and connecting rods. It also details the lubrication, cooling, fuel and electrical systems, plus the air inlet and exhaust.
The maintenance standards and tightening torque sections give the wear limits, clearances and torque values you need for a correct rebuild, and a maintenance chart lists the service intervals. It is delivered as a downloadable PDF you can read on any device or print at the bench.
What's Inside This Manual
| System | Pages | Key Topics |
|---|---|---|
| Main Page | 1-4 | Introduction, How to Use This Manual, Fuel Injection Pump, Governor, And Turbocharger Coverage, Manual Sections and Contents in Index, References for Operation, Parts |
| - General Information | 5-12 | General (S4K-T Diesel Engine - External Views, S6K-T Diesel Engine - External Views, Engine Serial Number Location, Engine Model and Application Codes), Specifications |
| - Maintenance Standards | 13-23 | Maintenance Standards, Important Bolts and Nuts, Standard Bolts, Standard Stud Bolts, Standard Plugs, Sealants |
| - Special Tools | 24-27 | |
| - General Instructions | 28-30 | S4K-T Diesel Engine - External Views, S6K-T Diesel Engine - External Views, Engine Serial Number Location, Engine Model and Application Codes |
| - Testing and Adjusting | 31-42 | Adjustments (Valve Clearance Inspection and Adjustment, Fuel System Priming, Fuel Injection Timing Inspection and Adjustment, No-Load Minimum Speed and Maximum Speed Setting Inspection and Adjustment, Fan Drive Belt Inspection and Adjustment) |
| - Engine Accessory Removal and Installation | 43-49 | Preparatory Steps, Engine Accessory Removal, Engine Accessory Installation |
| - Engine Proper | 50-95 | Cylinder Heads and Valve Mechanism (Disassembly, Repair, Reassembly), Flywheel, Timing Gears and Camshaft (Disassembly, Pistons, Connecting Rods |
| - Air Inlet and Exhaust System | 96-98 | Paper-Element Type Air Cleaner (Disassembly and Inspection), Exhaust Manifold (Inspection) |
| - Lubrication System | 99-107 | Oil Pump (Disassembly, Repair, Reassembly), Oil Filter (Disassembly and Inspection), Pressure Relief Valve (Inspection), Relief Valve (Inspection) |
| - Cooling System | 108-114 | Water Pump (Disassembly, Inspection, Reassembly), Thermostat (Inspection), Radiator, Fan and Fan Belt (Inspection) |
| - Fuel System | 115-119 | Fuel Filter (Disassembly and Inspection), Fuel Injection Nozzles (Disassembly, Repair, Reassembly) |
| - Electrical System | 120-133 | Starter (Disassembly, Repair, Reassembly), Alternator (Disassembly, Inspection, Heater Relay (Inspection), Air Heater (Inspection) |
| - Workshop Theory | 134-137 | Heater Relay, Air Heater |
| -Maintenance Chart | 138-148 | Every 50 Service Hours, Every 250 Service Hours, Every 500 Service Hours, Every 1000 Service Hours, Every 2 Years, As Required |
Quick Reference Specifications
| Specification | Value | Page |
|---|---|---|
| All Models | ||
| Cylinder head bolts tightening torque | 12±0.5 kgf·m (87±3.6 lbf·ft) [118±5 N·m] | p. 21 |
| Fuel filter replacement interval | every 500 hours | p. 116 |
| Fuel filter element tightening torque | 39±5 N·m (4±0.5 kgf·m) | p. 117 |
| Fuel injection nozzle valve opening pressure (Nominal Value) | 220 (3128) [21.6] kgf/cm² (psi) [MPa] | p. 15 |
| Fuel injection nozzle spray angle | 155° | p. 15 |
| Air cleaner element replacement interval | every 1000 hours | p. 97 |
| Air cleaner clamp tightening torque | 0.5±0.1 kgf·m (3.6±0.7 lbf·ft) [4.9±1.0 N·m] | p. 97 |
| Thermostat valve opening temperature | 71±2 (159.8±3.6) °C (°F) | p. 15 |
| Thermostat temperature at which valve lifts more than 10 mm (0.4 in.) | 85°C (185°F) | p. 15 |
| Fan drive belt tension (deflection) | 12 (0.473) mm (in.), approx. | p. 14 |
| S4K | ||
| Water pump delivery capacity at 1800 rpm, S4K | 130 (34.3) liter (U.S. gal)/min | p. 15 |
| S4K-T | ||
| Water pump delivery capacity at 1800 rpm, S4K-T | 145 (38.3) liter (U.S. gal)/min | p. 15 |
