Yanmar 6LY3-STP, 6LY3-UTP, 6LY3-ETP Service Manual

M2215-04E150

6LY3-ETP/- STP/-UTP6LY3-ETP/- STP/-UTP

Printed in Japan

M2215-04E150

Publication No. M2215-04E150

History of Revision

Manual Name Service Manual for Marine Diesel Engine

Engine Model: 6LY3-ETP/-STP/-UTP

Number

of

revision

Date of

revision

Reason for

correction

Outline of correction

Correction item

No (page)

Corrected

by

New edition: November 2005

FOREWORD

This service manual has been compiled for engineers engaged in sales, service, inspection and
maintenance. Accordingly, descriptions of the construction and functions of the engine are emphasized
in this manual, while items, which should already be common knowledge, are omitted.

One characteristic of a marine diesel engine is that its performance in a vessel is governed by the
applicability of the vessel's hull construction and its steering system.

Engine installation, fitting out and propeller selection have a substantial effect on the performance of the
engine and the vessel. Moreover, when the engine runs unevenly or when trouble occurs, it is essential
to check a wide range of operating conditions - such as installation to the full and suitability of the ship's
piping and propeller - and not just the engine itself. To get maximum performance from this engine, you
should completely understand its functions, construction and capabilities, as well as proper use and
servicing.

Use this manual as a handy reference in daily inspection and maintenance, and as a text for engineering
guidance.

©2005 YANMAR CO., LTD
All rights reserved. This manual may not be
reproduced or copied, in whole or in part,
without the written permission of YANMAR
CO., LTD.

CONTENTS

1. General ............................................................................................................................ 1

1.1 Exterior views ..............................................................................................................1

1.2 Main specifications ...................................................................................................... 2

1.3 Fuel oil, lubricating oil and cooling water ....................................................................3

1.3.1 Fuel oil................................................................................................................... 3

1.3.2 Lubricating oil ........................................................................................................ 5

1.3.3 Cooling water ........................................................................................................ 7

1.4 Engine outline .............................................................................................................8

1.5 Piping diagrams ........................................................................................................10

1.6 Exhaust gas emission regulation .............................................................................. 11

1.6.1 Engine identification ............................................................................................ 11

1.6.2 EPA exhaust gas emission standard .................................................................. 12

1.6.3 EPA guarantee conditions for emission standard ............................................... 13

2. Inspection and adjustment .............................................................................................14

2.1 Periodic maintenance schedule ................................................................................ 14

2.2 Periodic inspection and maintenance procedure ...................................................... 16

2.2.1 Check before starting .......................................................................................... 16

2.2.2 Inspection after initial 50 hours or one month operation ..................................... 20

2.2.3 Inspection every 50 hours or monthly ................................................................. 22

2.2.4 Inspection on initial 250 hours or one year.......................................................... 27

2.2.5 Inspection every 250 hours or one year .............................................................. 33

2.2.6 Inspection every year .......................................................................................... 39

2.2.7 Inspection every 500 hours or two years............................................................. 41

2.2.8 Inspection 2,000 hours or every two years.......................................................... 42

2.2.9 Inspection every 1,000 hours or four years ......................................................... 43

2.2.10 Inspection every 2000 hours or eight years ...................................................... 45

2.3 Adjusting the no-load minimum speed ......................................................................49

2.4 Thermostat inspection ............................................................................................... 50

2.5 Test running .............................................................................................................. 51

2.5.1 Preliminary precautions....................................................................................... 51

2.5.2 Test running procedure ....................................................................................... 51

2.5.3 Check points and precautions during running ..................................................... 52

2.6 Long storage ............................................................................................................. 53

3. Troubleshooting .............................................................................................................54

3.1 Preparation before troubleshooting ........................................................................... 54

3.2 Quick reference chart for troubleshooting ................................................................. 55

3.3 Trouble code ............................................................................................................. 64

4. Disassembly and reassembly ........................................................................................ 65

4.1 Disassembly and reassembly precautions ................................................................ 65

4.2 Disassembly and reassembly tools ........................................................................... 66

4.2.1 General hand tools .............................................................................................. 66

4.2.2 Special hand tools ............................................................................................... 68

4.2.3 Measuring instruments ........................................................................................ 71

4.2.4 Other material...................................................................................................... 75

4.3 Disassembly and reassembly ................................................................................... 77

4.3.1 Disassembly ........................................................................................................ 77

4.3.2 Reassembly......................................................................................................... 83

5. Inspection and servicing of basic engine parts ............................................................ 103

5.1 Cylinder block .........................................................................................................103

5.1.1 Inspection of parts ............................................................................................. 103

5.1.2 Cleaning of oil holes .......................................................................................... 103

5.1.3 Color check procedure ...................................................................................... 104

5.1.4 Replacement of plugs........................................................................................ 105

5.1.5 Cylinder bore measurement .............................................................................. 106

5.2 Cylinder head .......................................................................................................... 107

5.2.1 Inspecting the cylinder head.............................................................................. 108

5.2.2 Valve seat correction procedure........................................................................ 109

5.2.3 Intake/exhaust valves, valve guides.................................................................. 111

5.2.4 Valve springs..................................................................................................... 114

5.2.5 Nozzle sleeve .................................................................................................... 116

5.2.6 Assembling the cylinder head ........................................................................... 117

5.2.7 Measuring top clearance ................................................................................... 118

5.2.8 Intake and exhaust rocker arms ........................................................................ 119

5.2.9 Adjustment of valve clearance .......................................................................... 120

5.3 Piston and piston pins ............................................................................................. 121

5.3.1 Piston ................................................................................................................ 121

5.3.2 Piston pin........................................................................................................... 123

5.3.3 Piston rings........................................................................................................ 124

5.4 Connecting rod ........................................................................................................ 127

5.4.1 Inspecting the connection rod ........................................................................... 127

5.4.2 Crank pin metal ................................................................................................. 129

5.4.3 Piston pin bushing ............................................................................................. 131

5.4.4 Assembling piston and connecting rod.............................................................. 132

5.5 Crankshaft and main bearing ..................................................................................133

5.5.1 Crankshaft ......................................................................................................... 133

5.5.2 Main bearing...................................................................................................... 135

5.6 Camshaft and Tappets ............................................................................................ 136

5.6.1 Camshaft ........................................................................................................... 136

5.6.2 Tappets ............................................................................................................. 138

5.7 Timing gear ............................................................................................................. 140

5.7.1 Inspecting the gears .......................................................................................... 140

5.7.2 Gear timing marks ............................................................................................. 141

5.8 Flywheel and housing .............................................................................................142

5.8.1 Specifications of flywheel .................................................................................. 142

5.8.2 Ring gear........................................................................................................... 143

5.8.3 Position of top dead center................................................................................ 143

6. Fuel injection equipment ..............................................................................................144

6.1 Fuel Injection pump/governor/timer ........................................................................144

6.1.1 Fuel system diagram ......................................................................................... 144

6.1.2 Fuel injection pump specifications..................................................................... 145

6.1.3 Removing a fuel injection pump assy................................................................ 146

6.1.4 Installing a fuel injection pump assy.................................................................. 149

6.1.5 Troubleshooting of fuel injection pump.............................................................. 157

6.2 Fuel Injection nozzle ...............................................................................................159

6.2.1 Functioning of fuel injection nozzle ................................................................... 159

6.3 Fuel feed pump ....................................................................................................... 161

6.3.1 Fuel feed pump specifications........................................................................... 162

6.3.2 Fuel feed pump disassembly............................................................................. 162

6.3.3 Fuel feed pump inspection ............................................................................... 163

6.3.4 Fuel feed pump reassembly ............................................................................. 163

6.3.5 Fuel feed pump adjustment .............................................................................. 164

6.4 Fuel filter .................................................................................................................166

6.4.1 Fuel filter specifications ..................................................................................... 166