Yanmar 4BY | 6BY Service Workshop Manual

Workshop Service and Repair Manual for the Yanmar 4BY & 6BY engines, an absolute must-have for any Yanmar owner. This full workshop manual covers every component, service and repair procedure in full Yanmar factory specification with clear step by step photographs and technical drawings for the Yanmar 4 and 6 cylinder engines with torque setting values throughout each chapter, this is the most comprehensive service manual available as used by boatyards and independent marine engineers the world over.

Below Is An Exhaustive List Of The Items Covered Within This Manual:

Engines:

4BY-150
4BY-180
6BY-220
6BY-260

General Service Information:
Safety Precautions
Engine Outline Drawings
4By With Kmh40A
6By With Kmh40A
Engine Piping Diagrams
Location Of Nameplates
Engine Nameplates (Typical)
Diesel Fuel
Diesel Fuel Specifications
Bleeding The Fuel System
Engine Oil
Engine Oil Specifications
Acceptable Engine Oil
Recommended Marine Gear Or Stern Drive Oil.
Recommended Power Steering Fluid
Engine Coolant
Engine Coolant Specifications
Acceptable Engine Coolant
Principal Engine Specifications
Tightening Torques For Standard Bolts And Nuts
Tightening Fasteners
Hexagon Bolts And Nuts
Hose Clamps
Prepare Engine For Long-term Storage
Abbreviations And Symbols

Periodic Maintenance:
Introduction
The Importance Of Periodic Maintenance
Performing Periodic Maintenance
Yanmar Replacement Parts
Required Epa Maintenance
Epa Requirements
Conditions To Ensure Compliance With Epa Emission Standards
Inspection And Maintenance
Periodic Maintenance Schedule
Periodic Maintenance Procedures
After Initial 50 Hours Of Operation
Every 50 Hours Of Operation
Every 250 Hours Of Operation
Every 500 Hours Of Operation
Every 1000 Hours Of Operation
Every 2000 Hours Of Operation
Engine
Before You Begin Servicing
Introduction
Specifications
General Information
Test And Adjustment Specifications
Repair Specifications
Special Torque Chart
Special Service Tools
Measuring Instruments
Sealants And Compounds
Tests And Adjustments
Test Compression

Cylinder Head:
Cylinder Head Components
General Guidelines
Remove And Install Cylinder Head Cover
Remove And Install Glow Plugs
Remove Cylinder Head
Disassemble Cylinder Head
Clean Cylinder Head Components
Pressure Test The Cylinder Head
Inspect Cylinder Head Components
Replace Valve Stem Seals
Assemble Cylinder Head
Determine Cylinder Head Gasket Thickness
Install Cylinder Head

Engine:
Pistons And Cylinders
Remove And Disassemble Piston And Connecting Rod
Inspect Pistons And Piston Rings
Assemble Piston And Connecting Rod
Install Piston And Connecting Rod
Flywheel And Flywheel Housing
Remove And Install Flywheel Housing
Remove And Install Drive Coupling
Remove Flywheel
Replace Rear Crankshaft Seal
Install Flywheel
Camshaft And Timing Gear Train
Components
Check And Adjust Camshaft Timing
Remove And Install Vibration Damper – 4By
Remove And Install Vibration Damper – 6By
Remove Timing Case Cover
Remove And Install Timing Chain
Install Timing Case Cover
Remove And Install Timing Chain Tensioner
Remove Camshafts
Install Camshafts
Cylinder Block And Crankshaft
Components
Remove Crankshaft.
Measure Oil Clearance
Inspect Crankshaft
Inspect Cylinder Block
Install Crankshaft
Replace Front Crankshaft Seal
Intake Manifold
Remove
Install
Exhaust Manifold
Remove
Install
Attach Engine To Repair Stand

Fuel System:
Safety Precautions
Introduction
Specifications
Test And Adjustment Specifications
Special Torque Chart
Special Service Tools
Fuel System Components
4By Engines
6By Engines
Fuel Flow Diagram
Tests And Adjustments
Measure Fuel Feed Pump Pressure
Test Return Fuel Pressure
Repair
Remove Fuel Injector
Clean Fuel Injector Cavities
Install Fuel Injector
Remove And Install High-pressure Fuel Lines
Replace The Fuel Feed Pump
Replace High-pressure Fuel Pump
Replace Fuel Filters
Remove And Install Fuel Rail.
Replace Injector Return Fuel Line
Bleed The Fuel System

Cooling System:
Before You Begin Servicing
Introduction
Specifications
Test And Adjustment Specifications
Repair Specifications
Special Torque Chart
Special Service Tools
Measuring Instruments
Cooling Flow Diagram
Tests And Adjustments
Pressure Test Cooling System And Filler Cap
Test Thermostat
Repair
Drain And Refill Seawater Cooling System
Check And Replace Zinc Anodes
Drain And Fill Closed Cooling System
Disconnect And Connect Quick-connect Fittings
Remove And Install Hydraulic Oil Cooler
Inspect And Clean Hydraulic Oil Cooler.
Remove And Install Charge Air Cooler
Disassemble And Assemble Charge Air Cooler
Remove And Install Heat Exchanger
Disassemble And Assemble Heat Exchanger
Remove And Install Coolant Pump
Remove And Install Thermostat
Seawater Pump

Lubrication:
Introduction
Specifications
Test And Adjustment Specifications
Special Torque Chart
Special Service Tools
Measuring Instruments
Tests And Adjustments
Engine Oil Flow
Check Engine Oil Pressure
Repair
Engine Lubrication System Components
Change Engine Oil And Replace Engine Oil Filter Elemen
Remove And Install Oil Cooler
Remove And Install Oil Filter Housing
Remove And Install Oil Sump
Oil Pump

Turbocharger:
Introduction
Specifications
Test And Adjustment Specifications
Special Torque Chart
Special Service Tools
Sealants And Compounds
Tests And Adjustments
Measure Charge Pressure
Adjust Charge Pressure – 4By
Repair
Remove Turbocharger
Install Turbocharger

Starter Motor:
Before You Begin Servicing
Introduction
Starter Motor Specifications
General Specifications
Special Torque Chart.
Starter Motor Troubleshooting
Remove And Install Starter Motor

Alternator:
Introduction
Specifications
General Specifications
Special Torque Chart.
Repair
Replace Alternator Belt
Remove And Install Alternator
Remove And Install Alternator Belt Tensioner

Electrical And ECU:
Introduction
Specifications
Special Torque Chart
Function Description – Engine Management System
Component Locations
Electrical Panel Connector (X1) Connections
Engine Control Unit (Ecu) Assignments
Component Tests
Relays
Oil Pressure Sensor
Fuel Injector
Engine Coolant Temperature Sensor
Fuel Rail Pressure Control Valve
Water-in-fuel Sensor
Crankshaft Speed Sensor
Glow Plug/ Control Unit
Fuel Temperature Sensor
Fuel Volume Regulator
Charge Air Temperature Sensor
Charge Air Pressure Sensor.
Fuel Rail Pressure Sensor.
Camshaft Speed Sensor
Throttle Position Sensor
Repair:
Replace Engine Control Unit (Ecu)
Replace Coolant Temperature Sensor
Replace Charge Air Pressure Sensor
Replace Charge Air Temperature Sensor
Replace Crankshaft Sensor
Replace Camshaft Sensor
Replace High-pressure Fuel Control Valve
Replace High-pressure Fuel Sensor
Replace Fuel Temperature Sensor
Replace Fuel Volume Regulator
Replace Oil Pressure Sensor

Troubleshooting:
Introduction
Engine Faults And Torque Limitations
Torque Limitation For Failed Sensors Mode
Torque Limitation For Smoke Limitation Mode
Torque Limitation For Overheat Protection Mode
Troubleshooting Chart
Starting Trouble
Exhaust Colour
Vibration – Drive Disengaged
Vibration – Drive Engaged
Engine Knocks
Low Power Output
Engine Overheat
Engine Runs Cold
Coolant Loss
Helm Panel Display
Trouble Codes
Working Procedure
Diagnostic Trouble Codes
After Troubleshooting Or Repair