Yanmar 6LY3-STP User 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

6.4.2 Fuel filter inspection .......................................................................................... 167
7. Intake and exhaust system .......................................................................................... 168
7.1 Intake system .......................................................................................................... 168
7.2 Exhaust system ....................................................................................................... 168
7.2.1 Mixing elbow inspection .................................................................................... 168
8. Lubrication system ....................................................................................................... 169
8.1 Lubrication system .................................................................................................. 169
8.2 Lube oil pump ......................................................................................................... 170
8.2.1 Lube oil pump construction ............................................................................... 170
8.2.2 Specifications of lube oil pump.......................................................................... 171
8.2.3 Lube oil pump disassembly and reassembly..................................................... 172
8.2.4 Oil pressure control valve construction ............................................................. 174
8.3 Lube oil filter ............................................................................................................175
8.3.1 Lube oil filter construction.................................................................................. 175
8.3.2 Lube oil filter replacement ................................................................................. 175
8.4 Lube oil cooler ......................................................................................................... 176
8.4.1 Lube oil cooler construction............................................................................... 176
8.4.2 Inspecting the lube oil cooler............................................................................. 176
8.5 Rotary waste oil pump (Optional) ............................................................................ 177
9. Cooling water system .................................................................................................. 178
9.1 Cooling water system .............................................................................................. 178
9.2 Seawater pump ....................................................................................................... 179
9.2.1 Specifications of seawater pump....................................................................... 179
9.2.2 Seawater pump disassembly ............................................................................ 180
9.2.3 Seawater pump Inspection................................................................................ 180
9.2.4 Seawater pump reassembly.............................................................................. 181
9.3 Fresh water pump ................................................................................................... 182
9.3.1 Fresh water pump construction ......................................................................... 182
9.3.2 Specifications of fresh water pump ................................................................... 183
9.3.3 Fresh water pump disassembly......................................................................... 183
9.3.4 Fresh water pump inspection ............................................................................ 184
9.4 Heat exchanger ....................................................................................................... 186
9.4.1 Heat exchanger construction............................................................................. 186
9.4.2 Specifications of heat exchanger ...................................................................... 186

9.4.3 Disassembly and reassembly............................................................................ 186
9.4.4 Heat exchanger inspection................................................................................ 187
9.5 Pressure cap and coolant recovery tank ................................................................. 188
9.5.1 Pressure cap construction................................................................................. 188
9.5.2 Pressure cap pressure control .......................................................................... 188
9.5.3 Pressure cap inspection .................................................................................... 189
9.5.4 Function of the coolant recovery tank ............................................................... 189
9.5.5 Specifications of coolant recovery tank ............................................................. 189
9.5.6 Mounting the coolant recovery tank .................................................................. 190
9.5.7 Precautions on usage of the coolant recovery tank .......................................... 190
9.6 Thermostat .............................................................................................................. 191
9.6.1 Functioning of thermostat.................................................................................. 191
9.6.2 Thermostat construction.................................................................................... 191
9.6.3 Characteristics of thermostat............................................................................. 192
9.6.4 Thermostat inspection ....................................................................................... 192
9.6.5 Testing the thermostat....................................................................................... 192
9.7 Seacock (Optional) ................................................................................................. 193
9.8 Bilge pump and bilge strainer (Optional) ................................................................. 194
9.8.1 Introduction........................................................................................................ 194
9.8.2 Description ........................................................................................................ 195
9.8.3 Cautions ............................................................................................................ 196
9.8.4 Assembly procedure.......................................................................................... 198
9.8.5 Cautions for Assembling ................................................................................... 200
9.8.6 Troubleshooting................................................................................................. 202
10. Turbocharger ............................................................................................................. 203
10.1 Construction and function ..................................................................................... 204
10.1.1 Outline ............................................................................................................. 204
10.2 Standards for maintenance and check ................................................................. 206
10.2.1 Standards for maintenance and check ........................................................... 206
10.2.2 Tightening torque ........................................................................................... 207
10.3 Periodical checking procedure .............................................................................. 208
10.3.1 Periodical checking interval............................................................................. 208
10.3.2 Checking procedure ....................................................................................... 208
10.4 Disassembly procedure ........................................................................................ 210
10.4.1 Preparations for disassembly .......................................................................... 210

10.4.2 Check before disassembly ............................................................................. 212
10.4.3 Disassembly ................................................................................................... 213
10.5 Cleaning and checking procedure ........................................................................ 215
10.5.1 Cleaning .......................................................................................................... 215
10.5.2 Checking procedure ....................................................................................... 217
10.6 Reassembling procedure ...................................................................................... 220
10.6.1 Preparations for reassembly ........................................................................... 220
10.6.2 Reassembling procedure ................................................................................ 220
10.7 Handling after reassembly ................................................................................... 223
10.7.1 Precautions for mounting the turbocharger to the engine ............................... 223
10.8 Troubleshooting .................................................................................................... 224
10.8.1 Exhaust gas is dense ...................................................................................... 224
10.8.2 Whitish exhaust gas ....................................................................................... 224
10.8.3 Too early oil shortage ..................................................................................... 225
10.8.4 Output drop .................................................................................................... 225
10.8.5 Poor follow-up of supercharger ...................................................................... 225
10.8.6 Unusual sound or vibration.............................................................................. 225
11. Reduction and reversing gear ................................................................................... 226
12. Remote control .......................................................................................................... 227
12.1 Electronic control system (ECS) ........................................................................... 227
12.1.1 Digital display .................................................................................................. 228
12.1.2 Rocker switch panel ........................................................................................ 230
12.1.3 Control head (Shift &Throttle).......................................................................... 231
13. Electrical system ........................................................................................................ 232
13.1 Electrical system ................................................................................................... 232
13.1.1 Wiring diagram ................................................................................................ 232
13.2 Battery ...................................................................................................................233
13.2.1 Construction ................................................................................................... 233
13.2.2 Battery capacity and battery cables ................................................................ 234
13.2.3 Inspection ....................................................................................................... 235
13.2.4 Charging ......................................................................................................... 237
13.2.5 Battery storage precautions ........................................................................... 238
13.3 Starting Motor ....................................................................................................... 239
13.3.1 Specifications .................................................................................................. 239

13.3.2 Characteristics................................................................................................. 239
13.3.3 Structure.......................................................................................................... 240
13.3.4 Wiring diameter of a starting motor ................................................................. 242
13.4 Alternator standard, 12V/80A ................................................................................ 243
13.4.1 Specifications .................................................................................................. 243
13.4.2 Structure.......................................................................................................... 244
13.4.3 Wiring diagram ................................................................................................ 245
13.4.4 Standard output characteristics....................................................................... 246
13.4.5 Inspection ........................................................................................................ 247
13.5 Warning devices ................................................................................................... 248
13.5.1 Sensor installation position.............................................................................. 248
13.5.2 Lube oil pressure sensor and boost sensor .................................................... 250
13.5.3 Temperature sensor for water, lube oil and fuel.............................................. 251
14. Service standards ...................................................................................................... 252
14.1 Engine tuning ........................................................................................................ 252
14.2 Engine body .......................................................................................................... 253
14.2.1 Cylinder head .................................................................................................. 253
14.2.2 Camshaft and gear train.................................................................................. 254
14.2.3 Cylinder block.................................................................................................. 255
15. Tightening torque for bolts and nuts .......................................................................... 258
15.1 Main bolt and nut .................................................................................................. 258
15.2 Standard bolts and nuts (without lube oil) ............................................................. 259