Mitsubishi S4S S6S Diesel Engine Service Manual 99616-10170 PDF Download

Description

Mitsubishi S4S and S6S Diesel Engine Service Manual — Complete Workshop Reference

This Mitsubishi diesel engine service manual covers the S4S, S4S-DT, S6S, and S6S-DT engine models. It is the full workshop reference for maintenance, overhaul, adjustment, and testing of these water-cooled, four-stroke, overhead-valve industrial diesel engines. Every procedure is supported by exploded views, assembly sequence diagrams, maintenance standards tables, and tightening torque specifications. The engine rotates counterclockwise as viewed from the flywheel side.

File Details

• Manual type: Service Manual (Workshop Manual)
• Brand: Mitsubishi
• Models covered: S4S, S4S-DT, S6S, S6S-DT
• Document number: 99616-10170
• Language: English
• Page count: 157
• File format: PDF

Chapters Covered

• 1. General
• 2. Maintenance Standards
• 3. Special Tools
• 4. Overhaul Instructions
• 5. Adjustments, Bench Test, Performance Tests
• 6. Engine Auxiliaries Removal and Installation
• 7. Engine Main Parts
• 8. Inlet and Exhaust System
• 9. Lubrication System
• 10. Cooling System
• 11. Fuel System
• 12. Electrical System
• 13. Workshop Tips

General and Specifications

The opening chapters introduce the external layout of both the S4S and S6S engines, including left and right side views showing major components such as the fuel injection pump, inlet manifold, water pump, thermostat, alternator, starter, oil filter, and flywheel. Engine serial number location and model code breakdown are provided. The specifications section covers cylinder bore and stroke (94 × 120 mm), piston displacement (3.331 L for S4S, 4.996 L for S6S), compression ratio (22:1), firing order (1-3-4-2 for S4S, 1-5-3-6-2-4 for S6S), valve timing, and direction of rotation. Detailed tables cover lubrication system, cooling system, fuel system, and electrical system capacities and ratings.

Maintenance Standards and Tightening Torques

This chapter is the measurement and tolerance reference for the entire engine. It lists nominal values, assembly standards, repair limits, and service limits for cylinder bores, main bearing clearances, crankshaft journals and crankpins, camshaft journals, valve stems and guides, piston diameters and ring clearances, connecting rod bushings, and tappet bores. The tightening torque tables cover important bolts and nuts — cylinder head, main bearing caps, connecting rod caps, flywheel, crankshaft pulley — as well as standard bolts, studs, and plugs. A sealants and lubricants table specifies where to apply Three Bond sealants during reassembly.

Overhaul and Adjustment Procedures

The overhaul section explains how to determine when an engine needs rebuilding — low compression pressure being the primary indicator — and provides step-by-step compression testing procedures for both direct injection and swirl chamber engines, including the special tool adaptors required. The adjustments chapter covers valve clearance setting (0.25 mm cold for both inlet and exhaust), fuel system bleeding, injection timing checking and adjustment, no-load minimum and maximum speed settings, governor adjustment, speed regulation measurement, and V-belt inspection. Bench testing procedures and performance test conditions are also included.

Engine Auxiliaries and Main Components

Removal and installation procedures are given for the turbocharger, exhaust manifold, fuel filter, fuel injection pipes, inlet manifold, fuel injection nozzles (both direct injection and swirl chamber types), glow plugs, fuel injection pump, oil cooler, oil filter, alternator, water pump, starter, thermostat, and oil pan. The engine main parts chapter covers disassembly, inspection, and reassembly of the cylinder head and valve mechanism, flywheel, damper, timing gears, camshaft, pistons, connecting rods, crankshaft, crankcase, and tappets. Exploded views show the assembly sequence and highlight inspection points during disassembly.

Systems: Lubrication, Cooling, Fuel, Electrical

The lubrication system chapter covers the oil pump, oil filter, oil cooler, oil pressure relief valve, and safety valve. The cooling system chapter covers the water pump and thermostat, including the wax pellet thermostat opening temperature (76.5°C ±1.5°C) and valve lift specifications. The fuel system chapter covers the fuel filter and injection nozzles, with injection pressure values for both direct injection and swirl chamber types. The electrical system chapter covers the starter (12V – 2.2 kW or 12V – 3 kW), alternator (12V – 50A), glow plugs, and the optional stop solenoid.

Workshop Tips and Special Tools

The final chapter provides basic recommended assembly procedures for oil seals, O-rings, bearings, split pins, and spring pins. The special tools chapter lists the required part numbers for tasks such as valve spring removal, valve guide replacement, piston ring installation, compression pressure measurement, camshaft bushing installation, and oil seal sleeve installation.

Why This Mitsubishi S4S S6S Service Manual Matters

Whether you are servicing a Mitsubishi S4S in a forklift, a S6S in a generator set, or a turbocharged S4S-DT in agricultural or construction equipment, having the correct specifications and procedures on hand prevents costly mistakes. This manual gives you the exact maintenance standards, torque values, and assembly sequences that Mitsubishi specified for these engines — not generic estimates or guesses.

With this Mitsubishi diesel engine service manual, you can perform valve clearance adjustments, fuel injection timing, compression testing, top-end overhauls, bottom-end rebuilds, and electrical system diagnostics with confidence. The exploded views and assembly sequence summaries make even complex jobs like timing gear replacement or crankshaft removal manageable. The maintenance standards tables let you quickly determine whether a part is within specification, needs repair, or must be replaced.

IMAGES PREVIEW

This is a digital PDF manual — available for instant download immediately after purchase. No shipping, no waiting for a physical book. View it on any device — computer, tablet, or smartphone — and print the pages you need for the workshop. Keep it on your shop computer or take it with you to the job site.