Iseki Shibaura N4LDI Diesel Engine Service Manual for TG6620 TG6670 Tractor Repair

Description

Iseki Shibaura N4LDI Engine Service Manual for TG6620 & TG6670 Tractors

This Iseki Shibaura N4LDI diesel engine service manual is the complete workshop guide for the IHI Shibaura N4LDI engine as fitted to Iseki TG6620 and TG6670 tractors. Whether you are servicing, repairing, or rebuilding the N4LDI-TA-4501 or N4LDI-TA-4502 engine, this manual provides the factory procedures, torque specifications, and diagnostic routines needed to complete the job correctly. From routine maintenance intervals to full engine disassembly and common rail system diagnosis, every section is written for the technician working on these specific Iseki tractor models.

File Details

• Manual Type: Engine Service Manual
• Brand: Iseki / IHI Shibaura
• Engine Model: N4LDI (N4LDI-TA-4501, N4LDI-TA-4502)
• Tractor Models: TG6620, TG6670
• Language: English
• Page Count: 124
• File Format: PDF

Chapters Covered

• 1. General — General notes before service, fundamental instructions on service, standard tightening torque, tightening torque of main parts, main specifications, parts name and position, summary of engine structure, disassembly diagram
• 2. Engine Maintenance — Before start, when engine service required, detail confirmation before disassemble, service interval, main parts disassembly/inspection/repair, assembly, wire harness clamp position
• 3. Engine Trouble Shooting
• 4. Service Standard Data
• 5. Diagnosis of Failure
• 6. IHI Shibaura Electronic Service Tool D — Introduction, install, instructions, appendix

The Iseki Shibaura N4LDI engine service manual opens with the complete engine specifications: the N4LDI is a water-cooled 4-cycle diesel with four vertical in-line cylinders, 84 mm bore by 100 mm stroke, 2216 cc displacement, and 18.0:1 compression ratio. Rated output is 44.7 kW for the TG6620 and 48.5 kW for the TG6670. The fuel system is a common rail design, and the engine uses a turbocharger with waste gate, a dry-type air cleaner, and a trochoidal oil pump for pressurized lubrication. The manual lists the complete lubricant circuit and main components, the air circuit with EGR system, the coolant circuit, the common rail injection system, and the emission control system with DOC.

Engine Structure and Systems

Detailed system descriptions help you understand how the N4LDI engine is put together before you start turning wrenches. The lubricant circuit section covers the suction filter and pipe, relief valve, oil pump, oil cooler, oil filter, and the flow of oil to the rocker arm assembly, bearings, turbocharger, and oil mist separator. The air circuit explains the turbocharger, throttle valve, EGR valve, EGR cooler, and oil mist separator operation. The coolant circuit describes the water pump, thermostat, thermostat case, and coolant flow through the cylinder block, cylinder head, EGR cooler, and oil cooler. The common rail injection system section covers the HP pump, common rail, injectors, fuel filter, and ECU control, including how injection pressure, timing, quantity, and frequency are managed electronically.

Maintenance and Service Intervals

The service interval chart in this N4LDI engine manual covers daily checks through to 3000-hour maintenance, including engine oil replacement, oil filter element replacement, fuel filter replacement, coolant replacement, air cleaner element service, valve clearance checks, and EGR system cleaning. The main parts disassembly, inspection, and repair section walks through the common rail system, speed sensor, radiator, oil mist separator, turbocharger, EGR valve, throttle valve, intake temperature sensor, boost pressure sensor, fuel pump, pre fuel filter, main fuel filter, common rail, injectors, glow plugs, water pump, water temperature sensor, thermostat, oil pressure unit, rocker arm assembly, cylinder head, valve seat, valve spring, G sensor, gear case, timing gear, HP pump, camshaft, oil pump, balancer assembly, piston and rings, relief valve, crankshaft, connecting rod, bearing holder, cylinder block, oil cooler, and flywheel. Each component entry includes inspection criteria, standard values, service limits, and repair or replacement guidance.

Diagnostics and Electronic Service Tool

The engine troubleshooting chapter lists common conditions such as engine not starting, starting motor not operating, engine stopping after starting, engine stopping at operating temperature, irregular engine speed, engine overheat, bad exhaust color, oil leakage from muffler, battery charging failure, and oil pressure lamp issues, along with their causes and remedies. The diagnosis of failure chapter explains the process of using the IHI Shibaura Electronic Service Tool D and performing diagnosis by legwork using the 5W1H method. The service tool section covers installation, user authentication, project screen, DTC screen, data monitor, active test, utility functions including injector compensation and fuel pump learning, EGR maintenance time reset, and system settings. The service standard data chapter provides a consolidated reference of inspection items, standard dimensions, repair values, and service limits for the engine, cylinder head, piston, connecting rod, main bearing system, valve system, lubrication system, fuel system, and cooling system.

Assembly and Wire Harness Routing

The assembly chapter covers crankshaft and bearing holder installation, cylinder block and bearing holder assembly, relief valve, oil seals, rear plate, flywheel, piston and connecting rod assembly, balancer assembly, suction filter and pipe, oil pan, level gauge, front plate, HP pump and pulser, camshaft, idle gear, oil pump, gear case, crankshaft pulley, oil filter, tappet, head gasket selection, head bolt tightening by angle method, rocker arm assembly, valve clearance adjustment, head cover, oil pressure unit, oil pipe, injector, common rail, glow plug, intake manifold, boost sensor, intake temperature sensor, exhaust manifold, EGR system, turbocharger, water pump, thermostat, DOC, fan belt, wire harness, and ECU. The wire harness clamp position section provides a visual reference for routing and securing the engine wiring harness correctly.

IMAGES PREVIEW

This Iseki Shibaura N4LDI TG6620 TG6670 engine service manual gives you the exact procedures, torque values, and service limits needed to maintain, diagnose, and repair the N4LDI diesel engine. Instead of guessing at specifications or relying on generic diesel engine advice, you work from the same reference used for these Iseki tractors. The manual covers the common rail system in detail, including injector compensation, fuel pump learning, and electronic service tool operations that are essential when working on modern electronically controlled diesel engines. Having the correct procedures matters because incorrect assembly or adjustment can lead to poor performance, fuel system damage, or repeat failures. This N4LDI repair manual is delivered as an instant PDF download, so you can access it immediately after purchase. No shipping, no waiting. Use it on any device — laptop, tablet, or smartphone — and print the pages you need for the workshop. The PDF format lets you search, zoom, and navigate quickly, making it practical for both routine service and major overhauls.