Page 1 series SERVICE MANUAL 4BY2 BY Service Manual 6BY2 P/N: 0BBY0-U00200 MARINE ENGINES...
Page 2 / or safely. Please contact an authorized Yanmar repair or service professional before working on your Yanmar product.
Page 3: Table Of Contents
Acceptable Engine Oil ............. 3-16 Recommended Marine Gear or Stern Drive Oil....... 3-18 Recommended Power Steering Fluid........3-18 Engine Coolant................3-19 Engine Coolant Specifications..........3-19 Acceptable Engine Coolant ............. 3-20 Principal Engine Specifications ............. 3-21 BY Service Manual © 2009 Yanmar Marine International...
Page 4 Safety Precautions ................4-3 Introduction..................4-3 The Importance of Periodic Maintenance........4-3 Performing Periodic Maintenance ..........4-3 Yanmar Replacement Parts ............4-3 Required EPA Maintenance ............4-3 EPA Requirements................4-3 Conditions to Ensure Compliance with EPA Emission Standards ............4-3 Inspection and Maintenance .............
Page 5 Remove Camshafts ..............5-51 Install Camshafts ..............5-54 Cylinder Block and Crankshaft ............5-56 Components ................5-56 Remove Crankshaft..............5-58 Measure Oil Clearance............5-59 Inspect Crankshaft..............5-61 Inspect Cylinder Block ............. 5-62 BY Service Manual © 2009 Yanmar Marine International...
Page 6 Safety Precautions ................7-3 Introduction..................7-4 Specifications .................. 7-4 Test and Adjustment Specifications .......... 7-4 Repair Specifications..............7-4 Special Torque Chart ..............7-4 Special Service Tools..............7-5 Measuring Instruments..............7-5 Cooling Flow Diagram ..............7-6 BY Service Manual © 2009 Yanmar Marine International...
Page 7 Introduction..................9-3 Specifications .................. 9-3 Test and Adjustment Specifications .......... 9-3 Special Torque Chart..............9-3 Special Service Tools..............9-4 Sealants and compounds..............9-4 Tests and Adjustments..............9-5 Measure Charge Pressure ............9-5 BY Service Manual © 2009 Yanmar Marine International...
Page 8 Fuel Temperature Sensor ............. 12-18 Fuel Volume Regulator............12-18 Charge Air Temperature Sensor ........... 12-19 Charge Air Pressure Sensor ..........12-19 High-Pressure Fuel Rail Pressure Sensor ......12-20 Camshaft Speed Sensor ............12-20 viii BY Service Manual © 2009 Yanmar Marine International...
Page 9 Engine Overheat..............13-8 Engine Runs Cold..............13-9 Coolant Loss................13-9 Helm Panel Display ..............13-9 Trouble Codes................13-10 Working Procedure..............13-10 Diagnostic Trouble Codes ............. 13-10 After Troubleshooting or Repair ..........13-14 BY Service Manual © 2009 Yanmar Marine International...
Page 11 Section 1 BY Service Manual INTRODUCTION This manual gives specific instructions for the Along with standard tools, Yanmar recommends the proper repair of Yanmar BY2 series marine use of special tools necessary to perform repairs engines. correctly. Please follow the procedures carefully to ensure Yanmar products are continuously undergoing quality service.
Page 12 Revision Control Table. Discard the older, obsolete information. Revision Control Table Revision Date New Page Numbers Initiating Remarks Revision Number Involved Dept. APR 2009 Initial release BY Service Manual © 2009 Yanmar Marine International...
Page 13: Safety
Section 2 BY Service Manual SAFETY Yanmar is concerned for your safety and the condition of your marine engine. Safety statements are one of the primary ways to call your attention to Indicates a hazardous situation which, if not the potential hazards associated with Yanmar avoided, will result in death or serious injury.
Page 14: Safety Precautions
• Safety signs and decals are additional reminders for safe operating and maintenance techniques. Wipe up all spills immediately. • Contact your Yanmar RHQ for additional training. NEVER refuel with the engine running. Crush Hazard When attaching an engine to a repair...
Page 15 ALWAYS stop the engine before beginning service. If the engine must be serviced while it is operating, remove all jewelry, tie back long hair and keep hands, other body parts and clothing away from moving / rotating parts. BY Service Manual © 2009 Yanmar Marine International...
Page 16 • NEVER connect the weld clamp to the engine or in a manner which would allow current to pass Shift the marine gear into the NEUTRAL position through a mounting bracket. any time the engine is at idle. BY Service Manual © 2009 Yanmar Marine International...
Page 17 Tool Hazard ALWAYS remove any tools or shop rags used during maintenance from the area before operation. BY Service Manual © 2009 Yanmar Marine International...
Page 18 Make sure the engine is installed on a level surface. safety features such as defeating the engine speed If a Yanmar Marine engine is installed at an angle limit control or the diesel fuel injection quantity that exceeds the specifications stated in the control.
Page 19: General Service Information
Recommended Power Steering Fluid........3-18 Engine Coolant................3-19 Engine Coolant Specifications..........3-19 Acceptable Engine Coolant ............. 3-20 Principal Engine Specifications ............. 3-21 Tightening Torques for Standard Bolts and Nuts ......3-23 Tightening Fasteners............... 3-23 BY Service Manual © 2009 Yanmar Marine International...
Page 20 Units of Length ................ 3-26 Units of Volume ............... 3-26 Units of Mass................3-26 Units of Force ................3-26 Units of Torque................ 3-26 Units of Pressure..............3-26 Units of Power ................. 3-26 Units of Temperature............... 3-26 BY Service Manual © 2009 Yanmar Marine International...
Page 21: Safety Precautions
Check the electrical harnesses for cracks, abrasions, and damaged or corroded connectors. NEVER turn off the battery switch (if equipped) or short the battery cables during operation. Damage to the electrical system will result. BY Service Manual © 2009 Yanmar Marine International...
Page 22: Engine Outline Drawings
GENERAL SERVICE INFORMATION Engine Outline Drawings ENGINE OUTLINE DRAWINGS Note: All dimensions are metric. Contact Yanmar Marine for the most current drawings. 4BY2 (Inboard) Figure 3-1 719 (28.3) 709 (27.91) 240 (9.44) 469 (18.46) 608 (23.93) 848 (33.38) 0006537 Figure 3-1 BY Service Manual ©...
Page 23: 4By2 (Stern Drive)
Engine Outline Drawings GENERAL SERVICE INFORMATION 12/05 4BY2 (Stern Drive) Figure 3-2 671 (26.41) 709 (27.91) 700 (27.56) 469 (18.46) 0006531 Figure 3-2 BY Service Manual © 2009 Yanmar Marine International...
Page 24: 6By2 (Inboard)
GENERAL SERVICE INFORMATION Engine Outline Drawings 6BY2 (Inboard) Figure 3-3 716 (28.19) 847.45 (33.36) 709 (27.91) 700 (27.56) 240 (9.45) 460 (18.11) 0006541 Figure 3-3 BY Service Manual © 2009 Yanmar Marine International...
Page 25: 6By2 (Stern Drive)
Engine Outline Drawings GENERAL SERVICE INFORMATION 12/05 6BY2 (Stern Drive) Figure 3-4 716 (28.19) 709 (27.91) 700 (27.56) 240 (9.45) 460 (18.11) 0006495 Figure 3-4 BY Service Manual © 2009 Yanmar Marine International...
Page 26: Engine Piping Diagrams
14 – High-Pressure Fuel Rail Pressure Sensor 7 – High-Pressure Fuel Common Rail 15 – High-Pressure Fuel Regulator 8 – Fuel Injection Line (ECU-Controlled) 9 – Fuel Injector 16 – Fuel Volume Regulator (ECU-Controlled) BY Service Manual © 2009 Yanmar Marine International...
Page 27: 6By2
14 – High-Pressure Fuel Rail Pressure Sensor 7 – High-Pressure Fuel Rail 15 – High-Pressure Fuel Regulator 8 – Fuel Injection Line (ECU-Controlled) 9 – Fuel Injector 16 – Fuel Volume Regulator (ECU-Controlled) BY Service Manual © 2009 Yanmar Marine International...
Page 28 11 – Engine Coolant Passages 5 – Engine Heat Exchanger 12 – Coolant Recovery Tank 6 – Exhaust Seawater Mixing Elbow 13 – Water Cooled Exhaust Manifold 7 – Exhaust / Seawater Exit 3-10 BY Service Manual © 2009 Yanmar Marine International...
Page 29: Location Of Nameplates
0 7 5 1 1 0 0 7 8 2 4 9 5 1 The typical location of the engine nameplates is shown for Yanmar 4BY2 Series marine engines (Figure 3-8). 6BY2 engines are similar. Figure 3-8Engine Data and Drive Information...
Page 30: Diesel Fuel
GENERAL SERVICE INFORMATION Diesel Fuel DIESEL FUEL Biodiesel Fuels Yanmar approves the use of biodiesel fuels that do Diesel Fuel Specifications not exceed a blend of 5% non-mineral oil based fuel with 95% standard diesel fuel. Such biodiesel Diesel fuel should comply with the following fuels are known in the marketplace as B5 biodiesel specifications.
Page 31 • The use of biodiesel fuels that do not comply with 8 – Fuel Shutoff Valve the standards as agreed to by the diesel engine *Note:Yanmar supplies a water separating pre-filter manufacturers and the diesel fuel injection for mounting by the installer. The engine is equipment manufacturers, or biodiesel fuels that also equipped with an on-engine fine filter.
Page 32: Bleeding The Fuel System
3. Select the oil viscosity based on the ambient temperature where the engine is being operated. See the SAE Service Grade Viscosity Chart (Figure 3-11). 4. Yanmar does not recommend the use of engine oil “additives.” 3-14 BY Service Manual...
Page 33 (-20°C) (-10°C) (0°C) (10°C) (20°C) (30°C) (40°C) (50°C) 0000005B Figure 3-11 Note: Yanmar recommends using genuine Yanmar Marine oil, specifically formulated for the BY2 engine. See Acceptable Engine Oil on page 3-16. NOTICE: If the equipment will be operated at temperatures outside the limits shown, special lubricants or starting aids must be used.
Page 34: Acceptable Engine Oil
Igol Process Compact P Igol France S.A. INA Futura Compact P INA Maziva Rijeka Jet Top Level ConocoPhillips GmbH Labo RC Fuchs Labo Auto S.A. Liqui Moly Longtime High Tech Liqui Moly 3-16 BY Service Manual © 2009 Yanmar Marine International...
Page 35 Veedol International Veedol Syntron Veedol International Veritas Syntolube Ölwerke Julius Schindler GmbH Wako’s Super Synthe Wako Chemical Co.Ltd Wintershall VIVA 1 Longlife SRS Schmierstoff Vertrieb GmbH Yacco VX 1600 Yacco S.A.S. BY Service Manual 3-17 © 2009 Yanmar Marine International...
Page 36: Recommended Marine Gear Or Stern Drive Oil
Recommended Marine Gear or Stern Drive Oil Refer to the documentation supplied with each marine gear or stern drive. Recommended Power Steering Fluid Refer to the documentation supplied with each stern drive. 3-18 BY Service Manual © 2009 Yanmar Marine International...
Page 37: Engine Coolant
LLC, as a harmful sludge may form. Mixing different brands of antifreeze may cause chemical reactions, and may make the antifreeze useless or cause engine problems. Remove scale from the cooling system periodically by flushing the system. BY Service Manual 3-19 © 2009 Yanmar Marine International...
Page 38: Acceptable Engine Coolant
Glysantin Protect Plus / G48 BASF GUSOFROST LV 505 Chemische Industrielle Gesellschaft Mobil Frostchutz 600 Mobil Schmierstoff GmbH Havoline AFC (BD04) Chevron Texaco/Arteco Mobil Frostschutz 600 ExxonMobil OMV Kühlerfrostschutz OMV AG Total Thermofreeze Plus Total 3-20 BY Service Manual © 2009 Yanmar Marine International...
Page 39: Principal Engine Specifications
Variable depending on rpm; 250 to 1600 bar (3626 to 23,206 psi) Injection Timing Variable (ECU-controlled) ECU Threshold Voltage 7.8 V Cooling System Closed cooling system with heat exchanger Coolant Capacity 10.0 L 13.0 L (Approximate) (10.6 qt) (13.7 qt) BY Service Manual 3-21 © 2009 Yanmar Marine International...
Page 40 Fuel temperature at the inlet of the fuel injection pump. 1 hp (metric horsepower) = 0.7355 kW *** 1080 rpm @ startup for alternator excitation. **** Capacity may vary depending on installation angle. 3-22 BY Service Manual © 2009 Yanmar Marine International...
Page 41: Tightening Torques For Standard Bolts And Nuts
ALWAYS install new hose clamps. Size Specification 5 mm Hex Head 1.0 to 1.5 N·m (8.9 to 13 in.-lb) 6 mm Hex Head 2.5 to 3.5 N·m (22 to 31 in.-lb) BY Service Manual 3-23 © 2009 Yanmar Marine International...
Page 42: Prepare Engine For Long-Term Storage
8. Waterproof the engine room to prevent rain or seawater from entering. 9. Charge the battery once a month to compensate for battery’s self-discharge. 10. Remove key from key switch and cover key switch with moisture cap (if equipped). 3-24 BY Service Manual © 2009 Yanmar Marine International...
Page 43: Abbreviations And Symbols
* Work torque such as engine torque Japanese Automobile ** Work torque such as starter motor torque JASO Standards Organization kilogram kilogram force per square kgf/cm² centimeter kgf·m kilogram force meter kilometers BY Service Manual 3-25 © 2009 Yanmar Marine International...
Page 44: Unit Conversions
4.4480 0.4536 = kgf Units of Temperature 0.2248 = lbf 0.1020 = kgf °F = (1.8 x °C) + 32 2.2050 = lbf °C = 0.556 x (°F - 32) 9.8070 3-26 BY Service Manual © 2009 Yanmar Marine International...
Page 45: Periodic Maintenance
Safety Precautions ................4-3 Introduction..................4-3 The Importance of Periodic Maintenance........4-3 Performing Periodic Maintenance ..........4-3 Yanmar Replacement Parts ............4-3 Required EPA Maintenance ............4-3 EPA Requirements................4-3 Conditions to Ensure Compliance with EPA Emission Standards ............4-3 Inspection and Maintenance............
Page 47: Safety Precautions
Note: Inspections are divided into two sections Yanmar Replacement Parts in accordance with who is responsible for performing the inspection: the user or the Yanmar recommends that you use genuine Yanmar maker. parts when replacement parts are needed. Genuine replacement parts help ensure long engine life.
Page 48: Inspection And Maintenance
This maintenance must be performed to keep the emission values of the engine in the standard values during the warranty period. The warranty period is determined by the age of the engine or the number of hours of operation. BY Service Manual © 2009 Yanmar Marine International...
Page 49: Periodic Maintenance Schedule
Initial 50 element Cooling Visual inspection of cooling System - system Before Engine Coolant starting Check coolant level and check for leaks Before starting Drain and refill closed cooling system (engine coolant) BY Service Manual © 2009 Yanmar Marine International...
Page 50 Replace the air filter element Electrical Check the electrolyte level System in the battery (serviceable batteries only) Check the wiring connectors Before starting Check alternator belt for wear or replace belt BY Service Manual © 2009 Yanmar Marine International...
Page 51 Check anodes periodically. Any anode having less than half its original size remaining should be replaced - use this to establish a regular replacement interval. Note: The above procedures are considered normal maintenance and are performed at the owner’s expense. BY Service Manual © 2009 Yanmar Marine International...
Page 52 Clean fuel injection nozzle 1500 hours Check fuel injection nozzle adjustment Check fuel injection pump adjustment 3000 hours Check turbocharger adjustment Check electronic engine control unit (ECU) and its associated sensors and actuators BY Service Manual © 2009 Yanmar Marine International...
Page 53: Periodic Maintenance Procedures
8. Install a new filter element. Ensure the filter fits snugly in the filter cap. 9. Install the cap and filter assembly. Tighten cap by hand until the seal touches the housing. 10. Tighten to 25 N·m (225 in.-lb). BY Service Manual © 2009 Yanmar Marine International...
Page 54: Every 50 Hours Of Operation
The battery electrolyte is dilute sulfuric acid and causes severe acid burns. If you come in contact with electrolyte, wash and rinse it off immediately with a large amount of fresh water and baking soda. 4-10 BY Service Manual © 2009 Yanmar Marine International...
Page 55: Every 250 Hours Of Operation
• Checking the Hydraulic Oil Cooler In such conditions, inspect the battery more often. • Checking or Replacing Rubber Hoses • Checking the Flexible Engine Mounts BY Service Manual 4-11 © 2009 Yanmar Marine International...
Page 56 8. Bleed the fuel system and check for leaks. See Bleed the Fuel System on page 6-22. Replacing the Fuel Filter / Water Separator Element Note: Yanmar supplies a water separating 0004542 pre-filter separate from the engine. Figure 4-4 Location and type of filter may vary.
Page 57 10. Ensure drain plug (Figure 4-6, (4)) is securely tightened. 11. Connect water sensor (Figure 4-6, (1)). 12. Open the fuel cock. 13. Connect the battery negative (-) cable. BY Service Manual 4-13 © 2009 Yanmar Marine International...
Page 58 3. Install each anode using a new copper gasket and tighten to 25 N·m (18 ft-lb). 4. Start engine and check for water leaks. Checking or Replacing the Seawater Pump Impeller See Seawater Pump on page 7-18. 4-14 BY Service Manual © 2009 Yanmar Marine International...
Page 59: Every 500 Hours Of Operation
Checking or Replacing Rubber Hoses Check rubber water and fuel hoses for wear or damage. Checking the Flexible Engine Mounts 0003660 Check the flexible engine mounts for wear or Figure 4-11 damage. BY Service Manual 4-15 © 2009 Yanmar Marine International...
Page 60 Carefully clean the filler cap and the surrounding area before you remove the cap. NEVER mix different types of engine coolants. This may adversely affect the properties of the engine coolant. 4-16 BY Service Manual © 2009 Yanmar Marine International...
Page 61: Every 1000 Hours Of Operation
Check flexible engine mounts for damage, cracks or wear. See Checking the Flexible Engine Mounts on page 4-15. Replacing the Seawater Pump Impeller See Checking or Replacing the Seawater Pump Impeller on page 4-14. BY Service Manual 4-17 © 2009 Yanmar Marine International...
Page 62 PERIODIC MAINTENANCE Periodic Maintenance Procedures This Page Intentionally Left Blank 4-18 BY Service Manual © 2009 Yanmar Marine International...
Page 63: Engine
Pressure Test the Cylinder Head ..........5-24 Inspect Cylinder Head Components........5-24 Replace Valve Stem Seals ............5-25 Assemble Cylinder Head ............5-26 Determine Cylinder Head Gasket Thickness......5-26 Install Cylinder Head ............... 5-27 BY Service Manual © 2009 Yanmar Marine International...
Page 64 Inspect Cylinder Block............. 5-62 Install Crankshaft..............5-62 Replace Front Crankshaft Seal ..........5-64 Intake Manifold ................5-66 Remove ................... 5-66 Install ..................5-67 Exhaust Manifold................5-69 Remove ................... 5-69 Install ..................5-69 BY Service Manual © 2009 Yanmar Marine International...
Page 65: Safety Precautions
SAFETY PRECAUTIONS INTRODUCTION Before servicing the engine, review the Safety This section of the Service Manual describes the Section on page 2-1. disassembly, inspection, and reassembly of the 4BY2 and 6BY2 engines. BY Service Manual © 2009 Yanmar Marine International...
Page 66: Specifications
2.993 L Effective Displacement (122 cu in.) (183 cu in.) Compression Ratio 16.5:1 16.5:1 Test and Adjustment Specifications Test Item Remarks Specification 28 ±2 bar Cylinder Compression Test Compression Pressure (406 ±29 psi) BY Service Manual © 2009 Yanmar Marine International...
Page 67: Repair Specifications
(1.020 ±0.004 in.) Head Diameter - Exhaust 25.9 ±0.1 mm (1.020 ±0.004 in.) Valves Stem Diameter - Intake 5.92 ±0.02 mm (0.233 ±0.0008 in.) Stem Diameter - Exhaust 5.92 ±0.02 mm (0.233 ±0.0008 in.) BY Service Manual © 2009 Yanmar Marine International...
Page 68 (1.7520 -0.0004 / -0.0010 in.) Radial Bearing Play 0.015 - 0.050 mm (0.0006 - 0.0020 in.) Maximum Permitted Radial Runout 0.40 mm Engine (0.016 in.) Vibration Maximum Permitted Axial Runout 0.40 mm Damper (0.016 in.) BY Service Manual © 2009 Yanmar Marine International...
Page 69 (0.006 in.) Includes Oil Filters 8.0 L 4BY2 (8.5 qt) Oil Change Volume 11.0 L 6BY2 (11.5 qt) Values are for new or reconditioned cylinders. Capacity may vary depending on installation angle BY Service Manual © 2009 Yanmar Marine International...
Page 70: Special Torque Chart
Plug to Timing Case Cover 4BY2 Replace Seal M30 x 1 70 N·m (52 ft-lb) 6BY2 Plug to Timing Case Cover 4BY2 Replace Seal M40 x 1.5 30 N·m (22 ft-lb) 6BY2 BY Service Manual © 2009 Yanmar Marine International...
Page 71 Sprocket to High-Pressure 4BY2 M14 x 1.5 65 N·m (48 ft-lb) Pump 6BY2 Fuel System Injection Pump Drive Fuel Measuring Valve to 4BY2 M5 x 20 6.6 N·m (58 in.-lb) High-Pressure Pump 6BY2 BY Service Manual © 2009 Yanmar Marine International...
Page 72 Grade 10.9 Coolant Return Pipe to Thermostat and Crankcase and Oil Filter 4BY2 M8x18 11 N·m (97 in.-lb) Coolant Pipes Housing Glow Plugs 4BY2 Glow Plugs 17.5 N·m (154 in.-lb) 6BY2 5-10 BY Service Manual © 2009 Yanmar Marine International...
Page 73: Special Service Tools
Note: The tool numbers used in this section are either Yanmar or BMW part numbers. Yanmar part numbers are referred to as Yanmar Part No. and BMW part numbers are referred to as OEM Part No. Tools not having part numbers must be obtained locally.
Page 74: Measuring Instruments
0000836 Depth Micrometer For measuring valve recession 0000837 Square For measuring valve spring inclination and straightness of parts 0000838 Torque Wrench For tightening nuts and bolts to the specified torque 0000840 5-12 BY Service Manual © 2009 Yanmar Marine International...
Page 75: Sealants And Compounds
Timing Case Cover - Guide Rail Pins Flywheel Bolts Copper Anti-Seize Exhaust Manifold - Mounting studs Cylinder Head Cover ® Three Bond 1207F (Yanmar Part No. 977770-1207F) or equivalent Timing Case Cover - Gasket BY Service Manual 5-13 © 2009 Yanmar Marine International...
Page 76: Tests And Adjustments
Figure 5-1 Figure 5-1 5. Turn engine with the starter motor until reading on gauge stabilizes. Note reading on the gauge. 6. Reset gauge and repeat procedure with the remaining cylinders. 5-14 BY Service Manual © 2009 Yanmar Marine International...
Page 77: Repair
9. Remove cooling system components from engine. 10. Drain engine oil into a suitable container. Remove oil filter. BY Service Manual 5-15 © 2009 Yanmar Marine International...
Page 78: Cylinder Head
12 – Head Gasket Identification Holes 5 – Cam Follower 13 – Cylinder Head 6 – Valve Spring Retainer 14 – Cylinder Head Bolt 7 – Valve Spring 15 – Bolt 8 – Valve Stem Seal 5-16 BY Service Manual © 2009 Yanmar Marine International...
Page 79: General Guidelines
5 – Crankcase Ventilation Diaphragm Housing sequence, working from the outer bolts toward 6 – Seal the center. 7 – Double-Ended Bolt 8 – Bolt 9. Remove cylinder head cover. 9 – Profile Gasket BY Service Manual 5-17 © 2009 Yanmar Marine International...
Page 80 ® 2. Apply a thin uniform bead of Three Bond and diagonally. 1207F (Yanmar part No. 977770-1207F) 5. Install rubber gasket and oil filler cap. approximately 2 mm (0.079 in.) high and 2 mm 6. Breather / blow-by spacer is a two-part (0.079 in.) wide at the transition to each end of...
Page 81: Remove And Install Glow Plugs
7. Install and lock connector to glow plug. 9. Remove the intake manifold. See Intake 8. Install intake manifold. See Intake Manifold on Manifold on page 5-66. page 5-66. 9. Connect battery negative (-) terminal. BY Service Manual 5-19 © 2009 Yanmar Marine International...
Page 82 Remove and Install Glow Plugs on page 5-19. Figure 5-12 14. Release the locks and disconnect coolant return pipe (Figure 5-12, (2)). See Disconnect and Connect Quick-Connect Fittings on page 7-11. 5-20 BY Service Manual © 2009 Yanmar Marine International...
Page 83 22. 6BY2 Engines: Remove cylinder head bolts in reverse sequence, beginning with number 14 (Figure 5-18). Figure 5-18 Figure 5-16 Figure 5-18 23. Remove cylinder head. 24. Remove the cylinder head gasket. BY Service Manual 5-21 © 2009 Yanmar Marine International...
Page 84: Disassemble Cylinder Head
2. Put special tool OEM No. 11 9 008 with straight of the arrows (Figure 5-22). Rotate cylinder surface on combustion chamber side of cylinder head 180° into service position. head (Figure 5-20). Figure 5-22 Figure 5-20 Figure 5-22 Figure 5-20 5-22 BY Service Manual © 2009 Yanmar Marine International...
Page 85 11. Remove valve stem seals. See Replace Valve locations. Stem Seals on page 5-25. Remove valve keepers (Figure 5-24). Figure 5-24 Figure 5-24 BY Service Manual 5-23 © 2009 Yanmar Marine International...
Page 86: Clean Cylinder Head Components
11 6 406, 11 6 407 and 11 6 408. NOTICE: Mark all valve train components so they can be installed in their original locations. Note: Record all measurements taken during inspection. 5-24 BY Service Manual © 2009 Yanmar Marine International...
Page 87: Replace Valve Stem Seals
Specifications with oil and install over tool. Remove special Inspection Item Limit tool OEM No. 11 1 960. Valve Guide Intake 0.5 mm Figure 5-30 Wear (0.020 in.) Exhaust Figure 5-30 BY Service Manual 5-25 © 2009 Yanmar Marine International...
Page 88: Assemble Cylinder Head
4. Rotate the crankshaft to bring piston to the top of its stroke. Figure 5-32 5. Install spring compressor OEM No. 11 9 015 on lever OEM No. 11 9 009 (Figure 5-32). 5-26 BY Service Manual © 2009 Yanmar Marine International...
Page 89: Install Cylinder Head
(0.028 to 0.033 in.) 0.83 to 0.93 mm 2-hole (0.033 to 0.037 in.) 4BY2 / 6BY2 0.93 to 1.04 mm 3-hole (0.037 to 0.041 in.) 1.04 to 1.24 mm 0-hole (0.041 to 0.049 in.) BY Service Manual 5-27 © 2009 Yanmar Marine International...
Page 90 Tighten all bolts an additional 90° Fifth Tighten all bolts an additional 90° Figure 5-37 7. Install the timing case cover screws Figure 5-386BY2 Engine (Figure 5-40, (1)) and tighten. Figure 5-40 Figure 5-38 Figure 5-40 5-28 BY Service Manual © 2009 Yanmar Marine International...
Page 91 OEM No. 11 5 180 (Figure 5-44). Figure 5-44 ( 1 ) ( 2 ) 0003767 Figure 5-42 12. Install coolant branch fitting (Figure 5-42, (1)) Figure 5-44 with a new seal and tighten bolts. BY Service Manual 5-29 © 2009 Yanmar Marine International...
Page 92 23. Connect wires (Figure 5-45, (2)) to oil pressure sender. 24. Install intake manifold. See Intake Manifold on page 5-66. 25. Install heat exchanger. See Remove and Install Heat Exchanger on page 7-13. 5-30 BY Service Manual © 2009 Yanmar Marine International...
Page 93: Pistons And Cylinders
Use a wooden dowel against the connecting rod if necessary. NOTICE: NEVER allow the connecting rod to contact the crankshaft journal during piston removal. Damage to the bearing journal may result. BY Service Manual 5-31 © 2009 Yanmar Marine International...
Page 94: Inspect Pistons And Piston Rings
Cannot be measured End Gap Piston-to- 0.15 mm Clearance Cylinder (0.006 in.) 2. Clean piston ring grooves using a piston ring groove cleaning tool. Follow tool manufacturer’s instructions for correct operation. 5-32 BY Service Manual © 2009 Yanmar Marine International...
Page 95: Assemble Piston And Connecting Rod
5. Orient the piston and connecting rod as shown for assembly (Figure 5-53). The arrow on top of the piston must point to the right when the connecting rod identification marks are visible. Figure 5-53 Figure 5-53 BY Service Manual 5-33 © 2009 Yanmar Marine International...
Page 96: Install Piston And Connecting Rod
4 – Oil Ring Expander Spring 3. Rotate the crankshaft so the journal for the piston being installed is near BDC. 4. Apply a light coat of clean engine oil to the bearing insert. 5-34 BY Service Manual © 2009 Yanmar Marine International...
Page 97 Figure 5-59 10. Check bearing oil clearance before proceeding. See Measure Oil Clearance on page 5-59. 11. Apply a light coat of clean engine oil to the bearing insert and crankshaft journal. BY Service Manual 5-35 © 2009 Yanmar Marine International...
Page 98 19. Install the cylinder head. See Install Cylinder install used connecting rod cap bolts. ALWAYS Head on page 5-27. install new bolts when installing connecting rod cap. Figure 5-63 Figure 5-63 5-36 BY Service Manual © 2009 Yanmar Marine International...
Page 99: Flywheel And Flywheel Housing
0006512 Figure 5-64 Figure 5-65Marine Gear Engines ( 5 ) ( 4 ) ( 3 ) ( 2 ) ( 5 ) ( 6 ) ( 1 ) 0006513 Figure 5-65 BY Service Manual 5-37 © 2009 Yanmar Marine International...
Page 100: Remove And Install Drive Coupling
2. Install coupler adapter and tighten eight bolts to 46 N·m specification. M10 Bolt (34 ft-lb) 15 N·m 3. Install coupler. Install bolts and washers. (133 in.-lb) 23 N·m M8 Bolt Tighten to specification. (204 in.-lb) 5-38 BY Service Manual © 2009 Yanmar Marine International...
Page 101: Remove Flywheel
5. Inspect the flywheel for damage. Install a new flywheel if the ring gear teeth are chipped, broken, or have become so worn that starter motor pinion will not engage properly. BY Service Manual 5-39 © 2009 Yanmar Marine International...
Page 102: Replace Rear Crankshaft Seal
(Figure 5-70, (1)) installed and is to be used during installation. Use only the supplied bushing as an installation tool. Keep the bushing as a special tool for use in future service. 5-40 BY Service Manual © 2009 Yanmar Marine International...
Page 103: Install Flywheel
4. Apply medium strength thread lock and sealer to the threads of the flywheel bolts (Figure 5-71, (1)). Install bolts and tighten to initial torque specification. NOTICE: NEVER reuse flywheel bolts. ALWAYS install new flywheel bolts. BY Service Manual 5-41 © 2009 Yanmar Marine International...
Page 104: Camshaft And Timing Gear Train
ENGINE Camshaft and Timing Gear Train CAMSHAFT AND TIMING GEAR TRAIN Components Figure 5-72 (22) (21) (20) (19) (18) (17) (16) (13) (12) (15) (14) (10) (11) 0004027 Figure 5-72 5-42 BY Service Manual © 2009 Yanmar Marine International...
Page 105 8 – Timing Case Cover Gasket 19 – Hydraulic Tensioner 9 – Timing Case Cover 20 – Pivot Pin 10 – O-Ring 21 – Upper Chain Tensioner 11 – Access Plug 22 – Sprocket Retaining Screw BY Service Manual 5-43 © 2009 Yanmar Marine International...
Page 106: Check And Adjust Camshaft Timing
6. Remove special tools. 7. Install cylinder head cover. Adjust Camshaft Timing 1. Rotate the crankshaft until No. 1 cylinder intake camshaft lobes are facing down. NOTICE: NEVER remove the camshaft sprocket bolts. 5-44 BY Service Manual © 2009 Yanmar Marine International...
Page 107 ( 2 ) 6. If camshaft is not in alignment, loosen two remaining bolts (Figure 5-79, (1)) to adjust. Figure 5-79 ( 1 ) ( 1 ) 0003771 Figure 5-77 0003775 Figure 5-79 BY Service Manual 5-45 © 2009 Yanmar Marine International...
Page 108: Remove And Install Vibration Damper - 4By2
Figure 5-82 5. Remove the vibration damper bolt. 6. Remove flywheel holder and remove damper. 7. Place vibration damper on crankshaft and install new bolt and washer until vibration damper is snug. 5-46 BY Service Manual © 2009 Yanmar Marine International...
Page 109: Remove And Install Vibration Damper - 6By2
Additional 60° 7. Install alternator and seawater pump belts. See Remove and Install Alternator on page 11-5 and Replace Seawater Pump Belt on page 7-19. 8. Connect battery negative (-) cable. BY Service Manual 5-47 © 2009 Yanmar Marine International...
Page 110: Remove Timing Case Cover
8. Remove front crankshaft seal. See Replace Front Crankshaft Seal on page 5-64. 9. Remove alternator belt tensioner. 10. 4BY2: Remove alternator. See Remove and Install Alternator on page 11-5. 0006524 Figure 5-86 5-48 BY Service Manual © 2009 Yanmar Marine International...
Page 111: Remove And Install Timing Chain
Note: Only a one-piece gasket is available for 4. Remove nut (Figure 5-87, (2)). timing case cover and water pump. When repairing timing chain cover only, detach seal at marked points. BY Service Manual 5-49 © 2009 Yanmar Marine International...
Page 112: Remove And Install Timing Chain Tensioner
Three Bond 1207F 15. Fill engine with coolant. See Drain and Fill (Yanmar part No. 977770-1207F) sealing agent Closed Cooling System on page 7-10. to gasket at ends (arrow) on both sides. 16. Connect battery negative (-) cable.
Page 113: Remove Camshafts
0003777 Figure 5-90 5. Rotate the crankshaft until No. 1 cylinder intake camshaft lobes are facing down. Figure 5-92 6. Remove one bolt (Figure 5-91, (1)). 8. Rotate crankshaft counterclockwise 45°. BY Service Manual 5-51 © 2009 Yanmar Marine International...
Page 114 If the crankshaft is turned past TDC, rotate two more turns (720°) to bring No. 1 piston back to TDC. Secure crankshaft in TDC position with flywheel holding tool (Figure 5-96). Figure 5-96 Figure 5-94 Figure 5-96 5-52 BY Service Manual © 2009 Yanmar Marine International...
Page 115 17. Release guide rails (Figure 5-98, (2)) from installed in their original locations. mount and remove. 21. Remove the intake (Figure 5-100, (2)) and exhaust (Figure 5-100, (3)) camshafts. BY Service Manual 5-53 © 2009 Yanmar Marine International...
Page 116: Install Camshafts
(Figure 5-103, (2)) for cylinder No. 1 will face the exhaust side of the engine. Note: The valves will hold the camshafts above the bearing seats until all bolts are tightened. 5-54 BY Service Manual © 2009 Yanmar Marine International...
Page 117 Install Alternator on page 11-5. 15. Fill engine with coolant. See Drain and Fill Closed Cooling System on page 7-10. 16. Install cylinder head cover. See Remove and Install Cylinder Head Cover on page 5-17. BY Service Manual 5-55 © 2009 Yanmar Marine International...
Page 118: Cylinder Block And Crankshaft
ENGINE Cylinder Block and Crankshaft CYLINDER BLOCK AND CRANKSHAFT Components Figure 5-105 (17) (16) (18) (12) (15) (13) (14) (12) (10) (11) 0004029 Figure 5-105 5-56 BY Service Manual © 2009 Yanmar Marine International...
Page 119 9 – Lower Main Bearing Inserts 18 – Main Bearing Cap Note: Service procedures for 4BY2 and 6BY2 engines are similar, therefore graphics shown will be representative and might not match the engine being serviced. BY Service Manual 5-57 © 2009 Yanmar Marine International...
Page 120: Remove Crankshaft
0.060 to 0.250 mm Crankshaft End Play (0.0024 to 0.0098 in.) ( 1 ) 0003797 Figure 5-106 10. Remove pistons and connecting rods. See Remove and Disassemble Piston and Connecting Rod on page 5-31. 5-58 BY Service Manual © 2009 Yanmar Marine International...
Page 121: Measure Oil Clearance
See Special Torque bearing inserts (Figure 5-109). Chart on page 5-8. Figure 5-109 5. Remove the bearing cap. Figure 5-109 14. Remove crankshaft. Inspect and measure crankshaft journals as required. BY Service Manual 5-59 © 2009 Yanmar Marine International...
Page 122 Figure 5-112 1 – Crankshaft 2 – Oil Clearance 3 – Bearing Inserts: Yellow, Green, White 4 – Bearing Cap • Ge = Yellow • Gn = Green • Ws = White 5-60 BY Service Manual © 2009 Yanmar Marine International...
Page 123: Inspect Crankshaft
44.75 -0.009 / -0.025 mm (1.7618 -0.0004 / -0.0010 in.) Size 2 44.50 -0.009 / -0.025 mm (1.7520 -0.0004 / -0.0010 in.) Radial Bearing Play 0.015 - 0.050 mm (0.0006 - 0.0020 in.) BY Service Manual 5-61 © 2009 Yanmar Marine International...
Page 124: Inspect Cylinder Block
(3.317195 ± 0.000276 in.) Permitted out of round of cylinder 0.005 mm bore (0.000197 in.) Figure 5-116 Permitted conicity of cylinder 0.01 mm bore (0.000393 in.) Values are for new or reconditioned cylinders. 5-62 BY Service Manual © 2009 Yanmar Marine International...
Page 125 7. Tighten bearing cap bolts to 22 N·m (16 ft-lb). 8. Loosen bolts of the thrust bearing retaining cap and tighten finger-tight. Figure 5-118 9. Move each end of the crankshaft to center thrust bearing. BY Service Manual 5-63 © 2009 Yanmar Marine International...
Page 126: Replace Front Crankshaft Seal
See Install Timing Case Cover on page 5-49. 18. Install vibration damper. See Remove and Install Vibration Damper - 4BY2 on page 5-46 or Remove and Install Vibration Damper - 6BY2 on page 5-47. 5-64 BY Service Manual © 2009 Yanmar Marine International...
Page 127 6. Wipe the sealing surface in the cover clean. case cover. Remove seal protector. NOTICE: NEVER touch the sealing lip of the new seal Figure 5-1234BY2 Engines with your fingers. Figure 5-123 BY Service Manual 5-65 © 2009 Yanmar Marine International...
Page 128: Intake Manifold
Disconnect charge air pipe (Figure 5-128, (4)) 13. Install belts. See Remove and Install Alternator and bracket (Figure 5-128, (5)). on page 11-5 and Replace Seawater Pump Belt on page 7-19. 5-66 BY Service Manual © 2009 Yanmar Marine International...
Page 129: Install
Figure 5-132 ( 1 ) ( 2 ) 0003782 Figure 5-130 9. Remove nuts (Figure 5-130, (2)). 0006645 10. Remove intake manifold. Figure 5-132 7. Secure inlet line clamp (Figure 5-132, (3)). BY Service Manual 5-67 © 2009 Yanmar Marine International...
Page 130 (Figure 5-133, (2)). 10. Secure injector harness to intake manifold and connect to fuel injectors. 11. Bleed the fuel system. See Bleed the Fuel System on page 6-22. 5-68 BY Service Manual © 2009 Yanmar Marine International...
Page 131: Exhaust Manifold
Nut Torque 6BY2 ( 1 ) 6. Install turbocharger. See Install Turbocharger on page 9-6. 7. Install heat exchanger. See Remove and Install Heat Exchanger on page 7-13. 0006654 Figure 5-134 BY Service Manual 5-69 © 2009 Yanmar Marine International...
Page 132 ENGINE Exhaust Manifold This Page Intentionally Left Blank 5-70 BY Service Manual © 2009 Yanmar Marine International...
Page 133 Replace the Fuel Feed Pump..........6-15 Replace High-Pressure Fuel Pump ......... 6-15 Replace Fuel Filters..............6-19 Remove and Install Fuel Rail........... 6-20 Replace Injector Return Fuel Line ........... 6-21 Bleed the Fuel System ............6-22 BY Service Manual © 2009 Yanmar Marine International...
Page 135: Safety Precautions
Before servicing the fuel system, review the Safety This section of the Service Manual describes the Section on page 2-1. procedures necessary to remove, install and repair fuel system components as used on the Yanmar 4BY2 and 6BY2 engines. BY Service Manual © 2009 Yanmar Marine International...
Page 136: Specifications
0.1 bar (3 in.Aq) (Maximum) Fuel Temperature Maximum before speed reduction begins 80°C (176°F) Note: Yanmar supplies a water separating pre-filter for mounting by the installer. The engine is also equipped with an on-engine fine filter. Special Torque Chart Lubricating Oil Application (Thread...
Page 137: Special Service Tools
Note: The tool numbers used in this section are either Yanmar or BMW part numbers. Yanmar part numbers are referred to as Yanmar Part No. and BMW part numbers are referred to as OEM Part No. Tools not having part numbers must be acquired locally.
Page 138: Fuel System Components
4 – High-Pressure Fuel Rail 5 – High-Pressure Fuel Rail Pressure Sensor 6 – High-Pressure Line from Pump 7 – Rubber Insulator 8 – High-Pressure Pump with Fuel Measuring Unit 9 – High-Pressure Fuel Regulator BY Service Manual © 2009 Yanmar Marine International...
Page 139: Fuel Flow Diagram
14 – High-Pressure Fuel Rail Pressure Sensor 7 – High-Pressure Fuel Rail 15 – High-Pressure Fuel Regulator 8 – Fuel Injection Line (ECU-Controlled) 9 – Fuel Injector 16 – Fuel Volume Regulator (ECU-Controlled) BY Service Manual © 2009 Yanmar Marine International...
Page 140 14 – High-Pressure Fuel Rail Pressure Sensor 7 – High-Pressure Fuel Rail 15 – High-Pressure Fuel Regulator 8 – Fuel Injection Line (ECU-Controlled) 9 – Fuel Injector 16 – Fuel Volume Regulator (ECU-Controlled) BY Service Manual © 2009 Yanmar Marine International...
Page 141: Tests And Adjustments
6. Repeat the procedure on the fuel outlet side of the fuel fine filter (Figure 6-6, (2)). Specification Inspection Item Specification Fuel Feed Pump Pressure 5.0 bar (73.0 psi) (Minimum) 0006655 Figure 6-5 BY Service Manual © 2009 Yanmar Marine International...
Page 142: Test Return Fuel Pressure
Feed Pump Pressure on page 6-9. 1. Assemble a tee, hose and 0 to 100 kPa (0 to 15 psi) pressure gauge. 2. Disconnect the hose from the fuel return line (Figure 6-8, (1)). 6-10 BY Service Manual © 2009 Yanmar Marine International...
Page 143: Repair
Figure 6-9 ( 1 ) ( 2 ) Figure 6-11 9. If injector gasket did not come out with injector, 0003677 remove it from the bottom of the injector seat. Figure 6-9 BY Service Manual 6-11 © 2009 Yanmar Marine International...
Page 144: Clean Fuel Injector Cavities
6. Push brush (Figure 6-13, (4)) into guide sleeve (special tool OEM No. 13 5 210) Figure 6-16 (Figure 6-13, (5)). 6-12 BY Service Manual © 2009 Yanmar Marine International...
Page 145: Install Fuel Injector
15. Check and delete any trouble codes that are registered in the ECU after the work has been completed. Figure 6-17 4. Place the retainer (Figure 6-17, (3)) on the injector as shown. BY Service Manual 6-13 © 2009 Yanmar Marine International...
Page 146: Remove And Install High-Pressure Fuel Lines
11. Open all fuel supply valves. 12. Connect the battery negative (-) cable. 13. Bleed fuel system. See Bleed the Fuel System on page 6-22. 14. Start engine and check for fuel leaks. 6-14 BY Service Manual © 2009 Yanmar Marine International...
Page 147: Replace The Fuel Feed Pump
14. Check and delete any trouble codes that are OEM No. 13 5 020. registered in the ECU after the work has been completed. BY Service Manual 6-15 © 2009 Yanmar Marine International...
Page 148 14. Remove three nuts (Figure 6-27, (1)). Figure 6-27 Figure 6-24 11. Thread special tool OEM No. 13 5 192 into timing case cover (Figure 6-25). Figure 6-25 Figure 6-27 Figure 6-25 6-16 BY Service Manual © 2009 Yanmar Marine International...
Page 149 13 5 192) installed. Figure 6-29 Figure 6-31 Note: The pump shaft may have a keyway cut into it but no key is used in this application. R13 0675A Figure 6-29 BY Service Manual 6-17 © 2009 Yanmar Marine International...
Page 150 Figure 6-33 ( 3 ) 0003687 Figure 6-35 8. Connect fuel return line and banjo bolt (Figure 6-35, (3)) with new seal washers. 9. Connect fuel supply line (Figure 6-35, (2)). 6-18 BY Service Manual © 2009 Yanmar Marine International...
Page 151: Replace Fuel Filters
8. Bleed the fuel system and check for leaks. See Bleed the Fuel System on page 6-22. Replace the Fuel Filter / Water Separator Note: Yanmar supplies a water separating pre-filter separate from the engine. Location and type of filter may vary.
Page 152: Remove And Install Fuel Rail
7. Remove bolts (Figure 6-39, (4)) and remove 13. Connect the battery negative (-) cable. fuel rail from engine. 14. Bleed fuel system and check for leaks. See Bleed the Fuel System on page 6-22. 6-20 BY Service Manual © 2009 Yanmar Marine International...
Page 153: Replace Injector Return Fuel Line
(Figure 6-40, (2)) from fuel injector top. Repeat with all fuel injectors. Figure 6-40 Figure 6-42 7. Assembly is in the reverse order from disassembly. 8. Open all fuel supply valves. Figure 6-40 BY Service Manual 6-21 © 2009 Yanmar Marine International...
Page 154: Bleed The Fuel System
4. Attempt to start the engine. If the engine does not start within a reasonable time, repeat steps 1 and 2 until the engine starts and runs. 6-22 BY Service Manual © 2009 Yanmar Marine International...
Page 155: Cooling System
Disassemble and Assemble Charge Air Cooler ...... 7-13 Remove and Install Heat Exchanger ........7-13 Disassemble and Assemble Heat Exchanger ......7-14 Remove and Install Coolant Pump .......... 7-15 Remove and Install Thermostat..........7-16 Seawater Pump ............... 7-18 BY Service Manual © 2009 Yanmar Marine International...
Page 157: Safety Precautions
NEVER mix different types of engine coolants. This may adversely affect the properties of the engine coolant. BY Service Manual © 2009 Yanmar Marine International...
Page 158: Introduction
Remove and Install Charge Air Cooler Bolt 46 N·m (34 ft-lb) Not Applied Charge Air Cooler on page 7-12 Check and Replace Anode 25 N·m (18 ft-lb) Not Applied Anodes on page 7-9 BY Service Manual © 2009 Yanmar Marine International...
Page 159: Special Service Tools
Note: The tool numbers used in this section are either Yanmar or BMW part numbers. Yanmar part numbers are referred to as Yanmar Part No. and BMW part numbers are referred to as OEM Part No. Tools not having part numbers must be obtained locally.
Page 160: Cooling Flow Diagram
11 – Engine Coolant Passages 5 – Engine Heat Exchanger 12 – Coolant Recovery Tank 6 – Exhaust Seawater Mixing Elbow 13 – Water Cooled Exhaust Manifold 7 – Exhaust / Seawater Exit BY Service Manual © 2009 Yanmar Marine International...
Page 161: Tests And Adjustments
2. Pump until the cap opens (Figure 7-3). Figure 7-3 Cooling System Use a cooling system tester with connections compatible with the Yanmar BY2 series cooling system. 1. Remove the filler cap from the heat exchanger. WARNING! Burn Hazard. NEVER remove the coolant filler cap if the engine is hot.
Page 162: Test Thermostat
NOTICE: Be sure O-ring is in place in the groove of housing. 5. Remove anodes from the engine heat exchanger (Figure 7-4, (4)) and charge air cooler (Figure 7-4, (5)) and allow water to drain from housings. BY Service Manual © 2009 Yanmar Marine International...
Page 163: Check And Replace Anodes
Tighten to 25 N·m (18 ft-lb). NOTICE: NEVER use thread sealer or thread sealing tape when installing anodes. Anodes must make good metal-to-metal contact to perform properly. 4. Start engine and check for water leaks. BY Service Manual © 2009 Yanmar Marine International...
Page 164: Drain And Fill Closed Cooling System
Replace cap. Never fill to the full line. 13. After filling an empty cooling system, test-run the engine for approximately 5 minutes and recheck the engine coolant level at the coolant recovery tank again. 7-10 BY Service Manual © 2009 Yanmar Marine International...
Page 165: Disconnect And Connect Quick-Connect Fittings
10. Add power steering fluid or marine gear oil as appropriate. 11. Start engine and check for water or hydraulic leaks. 12. Check level of power steering fluid or marine gear oil and add more if necessary. BY Service Manual 7-11 © 2009 Yanmar Marine International...
Page 166: Inspect And Clean Hydraulic Oil Cooler
10. Tighten mounting bolts to 46 N·m (34 ft-lb). 11. Install pipe between intake manifold and charge air cooler. 12. Install and secure air inlet pipe between turbocharger and charge air cooler. 7-12 BY Service Manual © 2009 Yanmar Marine International...
Page 167: Disassemble And Assemble Charge Air Cooler
7. Remove the heat exchanger. 8. If any internal deposits remain in the tubes, consult a local radiator repair shop. Note: ALWAYS install new O-rings. 9. Install new O-rings (Figure 7-13, (2)) on cooler core. BY Service Manual 7-13 © 2009 Yanmar Marine International...
Page 168: Disassemble And Assemble Heat Exchanger
9. Install new O-rings (Figure 7-16, (4)) on cooler core. 10. Install cooler core and inlet cover (Figure 7-16, (5)). 11. Install one O-ring (Figure 7-16, (3)) between core and housing (Figure 7-16, (8)). 7-14 BY Service Manual © 2009 Yanmar Marine International...
Page 169: Remove And Install Coolant Pump
Note: Coolant pump cover is shown removed for clarity Figure 7-17. 6. Remove the four coolant pump bolts (Figure 7-17, (1)) and remove the coolant pump. Figure 7-17 0006524 Figure 7-19 Figure 7-17 BY Service Manual 7-15 © 2009 Yanmar Marine International...
Page 170: Remove And Install Thermostat
4. Remove coolant hose (Figure 7-21, (2)) connecting thermostat housing to the coolant pump. To release the clips on the coolant hose see, Disconnect and Connect Quick-Connect Fittings on page 7-11. 7-16 BY Service Manual © 2009 Yanmar Marine International...
Page 171 6. Test thermostat as required. See Test necessary. Thermostat on page 7-8. Replace as needed. Note: When replacing the thermostat or housing, replace as an assembly. The thermostat and housing are serviced as a single assembly. BY Service Manual 7-17 © 2009 Yanmar Marine International...
Page 172: Seawater Pump
Seawater Pump Belt on page 7-19. ( 1 ) 0003657 Figure 7-25 4. Remove the impeller (Figure 7-25, (2)) from the housing. 5. Inspect the impeller for cracks, broken vanes, or excessive wear. Replace as necessary. 7-18 BY Service Manual © 2009 Yanmar Marine International...
Page 173 NOTICE: Ensure belt is correctly engaged in all grooves of both pulleys. 9. Connect battery negative (-) cable. 8. Install belt guard. 9. Connect battery negative (-) cable. Start engine and verify pump operation. BY Service Manual 7-19 © 2009 Yanmar Marine International...
Page 174 COOLING SYSTEM Repair This Page Intentionally Left Blank 7-20 BY Service Manual © 2009 Yanmar Marine International...
Page 175: Lubrication
Change Engine Oil and Replace Engine Oil Filter Element ..8-9 Remove and Install Oil Cooler........... 8-9 Remove and Install Oil Filter Housing ........8-11 Remove and Install Oil Sump ..........8-11 Oil Pump.................. 8-12 BY Service Manual © 2009 Yanmar Marine International...
Page 177: Safety Precautions
Before servicing the BY2 marine engine lubrication This section of the Service Manual describes the system, review the Safety Section on page 2-1. procedures necessary to service the 4BY2 and 6BY2 lubrication systems. BY Service Manual © 2009 Yanmar Marine International...
Page 178: Specifications
Remove and Install Oil Sump on page 8-11 Oil Sump Drain Plug 25 N·m (221 in.-lb) Not Applied Oil Pickup Bolts 10 N·m (89 in.-lb) Not Applied Install Oil Pump on page 8-12 BY Service Manual © 2009 Yanmar Marine International...
Page 179: Special Service Tools
Note: The tool numbers used in this section are either Yanmar or BMW part numbers. Yanmar part numbers are referred to as Yanmar Part No. and BMW part numbers are referred to as OEM Part No. Tools not having part numbers must be obtained locally.
Page 180: Tests And Adjustments
11 – Port to Turbocharger Lubrication Line and 5 – Crankshaft Bearings Oil Pressure Sensor Line 6 – Oil Galley for Pressure Regulator Valve 12 – Piston Cooling Oil Pressure Regulator 7 – Oil Pump BY Service Manual © 2009 Yanmar Marine International...
Page 181: Check Engine Oil Pressure
3.8 to 6.0 bar 4000 rpm (55 to 87 psi) Figure 8-3 Note: Special tools OEM No. 13 6 054 and 13 6 051, and O-ring (Figure 8-4, (1)) are used with a DIS Tester. BY Service Manual © 2009 Yanmar Marine International...
Page 182: Repair
7 – Turbocharger Lubrication Return Line 3 – Oil Pressure Sensor 8 – Oil Pump 4 – Oil Pressure Sensor Line 9 – Oil Pickup and Screen 5 – Turbocharger Lubrication Supply Line BY Service Manual © 2009 Yanmar Marine International...
Page 183: Change Engine Oil And Replace Engine Oil Filter Element
8-6, (2))and filter assembly. Cooling System on page 7-10. 6. Remove the filter element from stem. 2. Remove oil filter element. See Change Engine Oil and Replace Engine Oil Filter Element on page 8-9. BY Service Manual © 2009 Yanmar Marine International...
Page 184 (Figure 8-9, (3)). 12. Install new oil filter element and tighten cap to 25 N·m (225 in.-lb). 13. Fill the engine with coolant. 14. Run engine and check for oil or water leaks. 8-10 BY Service Manual © 2009 Yanmar Marine International...
Page 185: Remove And Install Oil Filter Housing
( 2 ) Replace Engine Oil Filter Element on page 8-9. 2. Remove bolt securing oil dipstick tube to oil filter housing. Remove oil dipstick tube from oil pan. 0003790A Figure 8-13 BY Service Manual 8-11 © 2009 Yanmar Marine International...
Page 186: Oil Pump
9. Connect oil dipstick tube to oil filter housing. 10. If removed, install oil drain plug and tighten to 25 N·m (221 in.-lb). 11. Fill engine with clean engine oil. 8-12 BY Service Manual © 2009 Yanmar Marine International...
Page 187: Turbocharger
Test and Adjustment Specifications .......... 9-3 Special Torque Chart..............9-3 Special Service Tools..............9-4 Sealants and compounds..............9-4 Tests and Adjustments..............9-5 Measure Charge Pressure ............9-5 Repair....................9-6 Remove Turbocharger .............. 9-6 Install Turbocharger ..............9-6 BY Service Manual © 2009 Yanmar Marine International...
Page 189: Safety Precautions
6BY2 to threads Turbocharger Oil Supply 4BY2 Replace banjo bolt 22 N·m (195 in.-lb) Line 6BY2 and sealing rings Turbocharger Oil Return 4BY2 Hose clamp 3 N·m (27 in.-lb) to Crankcase 6BY2 BY Service Manual © 2009 Yanmar Marine International...
Page 190: Special Service Tools
Note: The tool numbers used in this section are either Yanmar or BMW part numbers. Yanmar part numbers are referred to as Yanmar Part No. and BMW part numbers are referred to as OEM Part No. Tools not having part numbers must be obtained locally.
Page 191: Tests And Adjustments
(4000 rpm) and take a reading after at least 30 seconds of constant operation. Results: If the reading is not within specification, adjust the control rod (4BY2) or replace the turbocharger. BY Service Manual © 2009 Yanmar Marine International...
Page 192: Repair
1. Clean mounting surfaces of all gasket material. (Figure 9-2, (3)) and return line (Figure 9-2, (4)) from the turbocharger. 5. Loosen and remove turbocharger-to-exhaust mixing elbow clamps and pull elbow away from turbocharger. BY Service Manual © 2009 Yanmar Marine International...
Page 193 7. Install air filter (Figure 9-5, (5)). 4. Connect charge air pipe (Figure 9-4, (1)) and 8. Connect exhaust mixing elbow to turbocharger tighten clamps securely. and tighten clamps securely. 9. Start engine and check for oil leaks. BY Service Manual © 2009 Yanmar Marine International...
Page 195: Starter Motor
STARTER MOTOR Page Safety Precautions ................ 10-3 Introduction..................10-3 Starter Motor Specifications ............10-3 General Specifications............. 10-3 Special Torque Chart............... 10-3 Starter Motor Troubleshooting............10-4 Remove and Install Starter Motor..........10-5 BY Service Manual 10-1 © 2009 Yanmar Marine International...
Page 197: Safety Precautions
Clockwise Clockwise Weight 3.5 kg (7.7 lb) 3.5 kg (7.7 lb) Special Torque Chart Item Specification Battery Positive (+) Cable 15 N·m (133 in.-lb) Solenoid Primary Wire 8 N·m (71 in.-lb) BY Service Manual 10-3 © 2009 Yanmar Marine International...
Page 198: Starter Motor Troubleshooting
STARTER MOTOR Starter Motor Troubleshooting STARTER MOTOR TROUBLESHOOTING Figure 10-1 0000102 Figure 10-1 10-4 BY Service Manual © 2009 Yanmar Marine International...
Page 199: Remove And Install Starter Motor
12. Operate starter to verify operation. 0003840 Figure 10-2 4. Remove bolts (Figure 10-3, (1)) securing the starter motor to the flywheel housing. Figure 10-3 ( 1 ) 0006653 Figure 10-3 BY Service Manual 10-5 © 2009 Yanmar Marine International...
Page 200 STARTER MOTOR Remove and Install Starter Motor This Page Intentionally Left Blank 10-6 BY Service Manual © 2009 Yanmar Marine International...
Page 201 Introduction..................11-4 Specifications ................11-4 General Specifications............. 11-4 Special Torque Chart............... 11-4 Repair.................... 11-5 Replace Alternator Belt............11-5 Remove and Install Alternator ..........11-5 Remove and Install Alternator Belt Tensioner ......11-6 BY Service Manual 11-1 © 2009 Yanmar Marine International...
Page 203: Safety Precautions
ALWAYS keep the connectors and terminals clean. NEVER use a high-pressure wash directly on the alternator. Water will damage the alternator and result in inadequate charging. BY Service Manual 11-3 © 2009 Yanmar Marine International...
Page 204: Introduction
Specification Manufacturer Valeo Model TG15 150A KSR-DF Nominal Voltage Nominal Output 150A Special Torque Chart Item Specification Alternator Mounting Bolts 38 N·m (28 ft-lb) Positive Cable Nut 13 N·m (115 in.lb) 11-4 BY Service Manual © 2009 Yanmar Marine International...
Page 205: Repair
4. Use a socket and breaker bar to rotate the belt tensioner and relieve belt tension. Remove belt. NOTICE: If belt is to be reused, note direction of travel and install in same direction of travel. BY Service Manual 11-5 © 2009 Yanmar Marine International...
Page 206: Remove And Install Alternator Belt Tensioner
4. Remove intake manifold. See Intake Manifold Figure 11-5 on page 5-66. 10. Installation is done in reverse of removal. Install 5. Remove alternator. See Remove and Install new seal (Figure 11-5, (2)). Alternator on page 11-5. 11-6 BY Service Manual © 2009 Yanmar Marine International...
Page 207: Electrical And Ecu
Throttle Position Sensor ............12-21 Repair..................12-22 Replace Engine Control Unit (ECU) ........12-22 Replace Coolant Temperature Sensor ........12-22 Replace Charge Air Pressure Sensor ........12-23 Replace Charge Air Temperature Sensor ......12-23 BY Service Manual 12-1 © 2009 Yanmar Marine International...
Page 208 Replace High-Pressure Fuel Regulator......... 12-25 Replace High-Pressure Fuel Rail Pressure Sensor ....12-26 Replace Fuel Temperature Sensor ........12-26 Replace Fuel Volume Regulator ........... 12-27 Replace Oil Pressure Sensor ..........12-27 12-2 BY Service Manual © 2009 Yanmar Marine International...
Page 209: Safety Precautions
Before servicing the electrical components, review the Safety Section on page 2-1. INTRODUCTION This section of the Service Manual describes the operation of and procedures to test and replace the components of the electrical system and engine control unit (ECU) as used on the Yanmar 4BY2 and 6BY2 marine engines. SPECIFICATIONS...
Page 210: Function Description - Engine Management System
ELECTRICAL AND ECU Function Description - Engine Management System FUNCTION DESCRIPTION - ENGINE MANAGEMENT SYSTEM Component Locations 4BY2 Figure 12-1 Figure 12-1 12-4 BY Service Manual © 2009 Yanmar Marine International...
Page 211 10 – Starter Motor 23 – High-Pressure Fuel Rail Pressure Sensor 11 – Crankshaft Speed Sensor 24 – Camshaft Speed Sensor 12 – Glow Plug Harness Connector 13 – Circuit Breaker (Boatbuilder Installed Option) BY Service Manual 12-5 © 2009 Yanmar Marine International...
Page 212 ELECTRICAL AND ECU Function Description - Engine Management System 6BY2 Figure 12-2 0004120 Figure 12-2 12-6 BY Service Manual © 2009 Yanmar Marine International...
Page 213 21 – Charge Air Temperature Sensor 11 – Crankshaft Speed Sensor 22 – Charge Air Pressure Sensor 12 – Glow Plug Harness Connector 23 – High-Pressure Fuel Rail Pressure Sensor 24 – Camshaft Speed Sensor BY Service Manual 12-7 © 2009 Yanmar Marine International...
Page 214: Electrical Panel Connector (X1) Connections
15 – Connector X22/1 - Fuel Injector Wiring Harness 16 – Blocking Diode V1 NOTICE: The electrical panel cables must be connected directly to the battery, and must have a circuit breaker installed in the B+ (red) lead. 12-8 BY Service Manual © 2009 Yanmar Marine International...
Page 215 Resistive Oil Sensor to Ground Input signal for CAN hub 0.5 A Gauge Water-in-Fuel Ground Signal if Water is in Fuel Input signal for CAN hub 0.1 A Sensor Not used BY Service Manual 12-9 © 2009 Yanmar Marine International...
Page 216: Engine Control Unit (Ecu) Assignments
(50) (22) (23) KL87 (24) (33) (51) (32) (25) X1/J (26) (30) X1/E (31) 202 204 206 KL31 (53) X1/Q X1/A X1/U (27) (52) (28) X1/S X1/T 0003303 (29) Figure 12-5 12-10 BY Service Manual © 2009 Yanmar Marine International...
Page 217 53 – NMEA Ground Supply 28 – CAN Signal - High 54 – Power Resistor for Generator NEVER connect any additional devices to F2. F6 may be used however, it is not switched. BY Service Manual 12-11 © 2009 Yanmar Marine International...
Page 218: Component Tests
1 – Pin 2 - terminal 87 (not used) 2 – Pin 4 - terminal 85 3 – Pin 5 - terminal 87 4 – Pin 6 - terminal 30 5 – Pin 8 - terminal 86 12-12 BY Service Manual © 2009 Yanmar Marine International...
Page 219 • P0690 - short circuit to B+ • P0231 - regulation short circuit to Ground Note: Viewed from bottom of connector. • P0232 - regulation short circuit to B+ Note: Viewed from bottom of connector. BY Service Manual 12-13 © 2009 Yanmar Marine International...
Page 220: Oil Pressure Sensor
2 – Pin 2 - High Side 1 – Engine Harness 2 – Engine Harness Note: Polarity of wire connections is not important. Either wire can be connected to either terminal. 12-14 BY Service Manual © 2009 Yanmar Marine International...
Page 221: Engine Coolant Temperature Sensor
1 – Pin 1 - Out (ECU pin 182) 0004169 2 – Pin 2 - Ground (ECU pin 17) Figure 12-12 1 – Pin 1 - 12V (Fuse F5) 2 – Pin 2 - Out (ECU pin 172) BY Service Manual 12-15 © 2009 Yanmar Marine International...
Page 222: Water-In-Fuel Sensor
The sensor signal is used by the ECU for: • The calculation of the actual rotations of the engine • The check of the starting conditions • The calculation of the injection rate at the starting procedure 12-16 BY Service Manual © 2009 Yanmar Marine International...
Page 223: Glow Plug / Control Unit
If the key switch is turned to ON but the engine is not started immediately, the controller will continue to implement the glowing process for 10 seconds. BY Service Manual 12-17 © 2009 Yanmar Marine International...
Page 224: Fuel Temperature Sensor
If this sensor is defective, the following P-codes • P0004 - short circuit to B+ may be generated: • P0088 - fuel rail pressure out of range • P0182 - short circuit to B+ 12-18 BY Service Manual © 2009 Yanmar Marine International...
Page 225: Charge Air Temperature Sensor
Vout is approximately 2.21 V • Resistance at 0°C (32°F): 14.5 to 16.5 k-ohm • Resistance at 20°C (68°F): 6.0 to 6.5 k-ohm • Resistance at 120°C (248°F): 0.18 to 0.22 k-ohm BY Service Manual 12-19 © 2009 Yanmar Marine International...
Page 226: High-Pressure Fuel Rail Pressure Sensor
3 – Pin 3 - Ground (ECU pin 115) • P0192 - short circuit to ground Test Values • At 0 bar (0 psi) (relative): 0.5 V • At 1800 bar (26107 psi) (relative): 4.5 V 12-20 BY Service Manual © 2009 Yanmar Marine International...
Page 227: Throttle Position Sensor
• P0222 - throttle signal 2 is missing / short circuit to ground Test Values • At 0 bar (0 psi) (relative) - 0.5 V • At 1800 bar (26 107 psi) (relative) - 4.5 V BY Service Manual 12-21 © 2009 Yanmar Marine International...
Page 228: Repair
7. Connect the electrical connectors to the ECU. 8. Connect the electrical panel power cables to the battery. 9. Check and delete any trouble codes that are registered in the ECU after the work has been completed. 12-22 BY Service Manual © 2009 Yanmar Marine International...
Page 229: Replace Charge Air Pressure Sensor
5. Install sensor and connect electrical connector. 6. Connect battery negative (-) cable. 7. Check and delete any trouble codes that are registered in the ECU after the work has been completed. BY Service Manual 12-23 © 2009 Yanmar Marine International...
Page 230: Replace Crankshaft Sensor
4. Install sensor and tighten screw to 2.3 N·m (20 in.-lb). 5. Connect harness connector. 6. Check and delete any trouble codes that are registered in the ECU after the work has been completed. 12-24 BY Service Manual © 2009 Yanmar Marine International...
Page 231: Replace High-Pressure Fuel Regulator
6-22. 14. Start engine and check for fuel leaks. 15. Check and delete any trouble codes that are registered in the ECU after the work has been completed. 0003684 Figure 12-31 BY Service Manual 12-25 © 2009 Yanmar Marine International...
Page 232: Replace High-Pressure Fuel Rail Pressure Sensor
10. Hold hex of sensor and tighten retaining nut to 11. Start engine and check for fuel leaks. 70 N·m (52 ft-lb). 11. Connect electrical connector to sensor. 12. Open all fuel supply valves. 12-26 BY Service Manual © 2009 Yanmar Marine International...
Page 233: Replace Fuel Volume Regulator
11. Bleed fuel system. See Bleed the Fuel System on page 6-22. 12. Start engine and check for fuel leaks. 13. Check and delete any trouble codes that are registered in the ECU after the work has been completed. BY Service Manual 12-27 © 2009 Yanmar Marine International...
Page 234 ELECTRICAL AND ECU Repair This Page Intentionally Left Blank 12-28 BY Service Manual © 2009 Yanmar Marine International...
Page 235: Troubleshooting
Engine Overheat..............13-8 Engine Runs Cold..............13-9 Coolant Loss................13-9 Helm Panel Display ..............13-9 Trouble Codes................13-10 Working Procedure..............13-10 Diagnostic Trouble Codes ............. 13-10 After Troubleshooting or Repair ..........13-14 BY Service Manual 13-1 © 2009 Yanmar Marine International...
Page 237: Safety Precautions
• Camshaft sensor • Boost pressure sensor • Rail pressure system • Throttle signal missing • Sensor supply voltage • Metering unit failure • Fuel injector failure • Rail pressure governor deviation BY Service Manual 13-3 © 2009 Yanmar Marine International...
Page 238 4BY2-150 100% (normal operation) 1600 Engine 4BY2-180 100% (normal operation) 1700 1050 Engine 6BY2-220 100% (normal operation) 2000 1100 1400 1100 Engine 6BY2-260 100% (normal operation) 2000 1100 1700 1400 1150 13-4 BY Service Manual © 2009 Yanmar Marine International...
Page 239: Torque Limitation For Overheat Protection Mode
Failed Sensors Mode on page 13-3. The substitute value of the fuel temperature is fixed at 90°C (194°F)and that sets a limitation of approximately 75% from the maximum torque (Figure 13-1). Figure 13-1 Figure 13-2 Figure 13-1 BY Service Manual 13-5 © 2009 Yanmar Marine International...
Page 240: Troubleshooting Chart
Cracked cylinder head Repair as necessary Cracked cylinder Worn piston rings / cylinders Oil leak in turbocharger (oil present in Blue Smoke Repair as necessary intake manifold) Damaged piston cooling nozzles 13-6 BY Service Manual © 2009 Yanmar Marine International...
Page 241: Vibration - Drive Disengaged
Bent propeller Replace as necessary Slipping clutch / clutch dog Repair as necessary Rough at Higher Speeds Check / replace fuel pressure regulator Incorrect injection pressure Check / replace high-pressure fuel pump BY Service Manual 13-7 © 2009 Yanmar Marine International...
Page 242: Engine Knocks
Damaged closed coolant pump Replace Combustion gas leakage (causes loss of Repair as necessary coolant) Seawater pump belt slips or pump pulley Repair as necessary loose on pump shaft Clogged heat exchanger Clean 13-8 BY Service Manual © 2009 Yanmar Marine International...
Page 243: Engine Runs Cold
Cracked cylinder wall Repair as necessary Leaking cylinder head gasket Replace Helm Panel Display Problem / Symptom Cause Action Harness connector loose Repair as necessary No Display Defective diode V1 Replace BY Service Manual 13-9 © 2009 Yanmar Marine International...
Page 244: Trouble Codes
Short circuit to Ground alarm P0004 Fuel Metering Unit Short circuit to B+ reduce alarm Rail Pressure Governor reduce or depends P0087 Fuel rail pressure out of range alarm Deviation shut off on fault 13-10 BY Service Manual © 2009 Yanmar Marine International...
Page 245 Throttle signal 2 short circuited to B+ reduce alarm P0230 Fuel Feed Pump Not connected alarm P0231 Fuel Feed Pump Short circuit to Ground reduce alarm P0232 Fuel Feed Pump Short circuit to B+ alarm BY Service Manual 13-11 © 2009 Yanmar Marine International...
Page 246 Not connected, short circuit alarm No. 2 Glow System - Glow Spark P0673 Not connected, short circuit alarm No. 3 Glow System - Glow Spark P0674 Not connected, short circuit alarm No. 4 13-12 BY Service Manual © 2009 Yanmar Marine International...
Page 247 * Relative value is the value read on a pressure gauge attached to the intake pipe. ** Absolute is the value reported by the ECU and displayed at the helm digital display. BY Service Manual 13-13 © 2009 Yanmar Marine International...
Page 248: After Troubleshooting Or Repair
REPAIR The engine control unit (ECU) may have generated trouble codes due to the current fault or during troubleshooting. Remember to check and clear any trouble codes after repairs are complete. 13-14 BY Service Manual © 2009 Yanmar Marine International...

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4by2 6by2

Yanmar BY Series Service Manual

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Engine

Fuel System

Cooling System

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Turbocharger

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