Mercury MERCRUISER - Front Mounts; Rear Mounts; Sterndrive Engine Mounts

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Sterndrive Engine Mounts

Front Mounts

a - Nylock top nut

b - Lock collar

c - Adjustment nut

Rear Mounts

NOTE: White or yellow paint is used to identify the top of the mount assembly. The bottom has a knurled edge.

Typical flywheel housing, all

similar

a - Painted end (not visible)

b - Mount bottom

c - Knurled edge

57661

57656

Engine Disassembly

Main Page

Important Information, Maintenance, and 17
- Table of Contents7
- Serial Number Decal Placement8
- Introduction8
- Engine Serial Number8
- Directional References9
- Seacore9
- Seacore Components and Castings9
- Stainless Steel Fasteners9
- Proper Break9
- 20-Hour Break-In Period9
- Gasoline Containing Alcohol10
- Using Reformulated (Oxygenated) Gasoline (USA Only)10
- Fuel Ratings10
- After the Break-In Period10
- Fuel Requirements10
- Engine Oil11
Important Information, Maintenance, and 117
- 6.2 MPI ECT and 6.2 MPI Non-ECT19
- Engine19
- Engine and Tune-Up Specifications19
- Fluid Specifications19
- Notes on Engine Specifications19
- Maintenance Intervals20
- Maintenance Schedule-Inboard Models20
- Power-Assisted Steering and Power Trim Fluids20
- Routine Maintenance20
- Scheduled Maintenance20
- Maintenance Schedule-Towsport Models21
- Routine Maintenance21
- Scheduled Maintenance21
- Maintenance Schedule-Sterndrive Models22
- Routine Maintenance22
- Scheduled Maintenance23
- Checking and Filling the Engine Oil24
- Engine Oil24
- Changing the Engine Oil and Filter25
- Transmission Fluid27
- Changing29
- Checking29
- Filling29
- Power Trim Fluid29
- Flame Arrestor30
- Serpentine Drive Belt31
- Inspection and Routing32
- Replacing Belt32
- Fuel System33
- Water-Separating Fuel Filter33
- Changing Coolant35
- Checking Coolant Level35
- Cleaning and Inspection35
- Closed-Cooling System35
- Power-Assisted Steering Fluid35
- Power-Assisted Steering Fluid-Sterndrive Only35
- Changing37
- Compact Hydraulic Steering37
- Bravo Sterndrive Gear Lube38
- Checking38
- Filling38
- System Check38
- Changing39
- Battery40
- Electrical System40
- Exhaust System40
- Instruments40
- Remote Control40
- Visual Inspections40
- Seawater Pump41
- Steering System Lubrication41
- Corrosion Prevention42
- Maintaining Ground Circuit Continuity42
- Mercathode44
- Power Package Exterior Surfaces44
- Cleaning the Seawater Strainer, if Equipped45
- Seawater System45
- Air Actuated Single-Point Drain System (Closed Cooling, Inboard Models)46
- Checking the Seawater Pickups46
- Draining the Raw Water46
- Draining the Seawater System46
- Air Actuated Single-Point Drain System (Standard Cooling)49
- Air Actuated Single-Point Drain System-Bravo Seawater Cooling52
- Draining the Sterndrive54
- Air Actuated Single-Point Drain System (Closed Cooling)55
- Draining the Raw Water55
- Draining the Seawater System55
- Air Actuated Single-Point Drain System (Closed Cooling, Inboard Models)58
- Flushing the Power Package61
- Flushing the Power Package (Bravo)61
- Seacore Power Package Flushing Procedure64
- Cold Weather or Extended Storage67
- Preparing Power Package for Storage-MPI Models67
- Power Package Recommissioning68
Important Information, Maintenance, and 171
- Before You Begin Troubleshooting72
- General Troubleshooting Guidelines72
- Introduction72
- Situational Awareness72
- Visual/Physical Check73
- Diagnostic Roadmap74
- Emission Control Fault Indicators74
- Chart R1: Engine System Fails to Power75
- Chart R2: OBD-M Lamp Does Not Self-Test76
- Chart R3: Crankshaft Fails to Rotate77
- Chart R4: Engine Cranks over but will Not Start78
- Chart R5: Hard Start79
- Chart R6: Engine Stalls80
- Chart S1: Engine Surges81
- Chart S2: Lack of Power, Sluggish, or Spongy81
- Diagnosis by Symptom81
- Chart S3: Detonation or Spark Knock82
- Chart S4: Hesitation, Sag, or Stumble84
- Chart S5: Engine Misses85
- Chart S6: Rough, Unstable, or Incorrect Idle and Stalling86
- Chart S7: Poor Fuel Economy86
- Chart S8: Dieseling or Run87
- Chart S9: Backfire88
- Chart T1: Main Power Relay Test89
- Troubleshooting Tests89
- Chart T2: Fuel System Electrical Test90
- Chart T3: Fuel System Diagnosis90
- Chart T4: Ignition System Test91
- CDS G3 Service Tool92
- Connecting and Starting G392
- Default Sensor Values92
- Fault Conditions92
- Introduction92
- OBD-M Faults92
- PCM 112 Calibration Information92
- Sticky and Nonsticky Faults92
- Troubleshooting Shift Problems92
- CDS G3 Service Tool Home Screen Overview94
- CDS G3 Fault List95
Removal and Installation 297
- Disconnecting the Fluid Systems98
- Fuel Hose98
- Preparation98
- Steering Hoses (Sterndrive)98
- Gear Lube Monitor (Sterndrive)99
- Seawater Hoses99
- Disconnecting the Shift Cable and Throttle Cable100
- Disconnecting the Electrical Components101
- Continuity Wire Removal (Sterndrive)102
- Removing the Engine102
Removal and Installation 2105
- Preparation107
- Torque Specifications107
- Engine Installation and Alignment (Sterndrive)108
- Shift Cable Routing108
- Bravo Seawater Inlet Fitting Connection113
- Connecting the Fluid Systems113
- Gear Lube Monitor Connection113
- Power-Assisted Steering Hoses116
- Speedometer and Pitot Connections116
- Bravo Models Remote Control Shift Cable Adjustment117
- Bravo Models Shift Cable Installation117
- Bravo Shift Cable Installation and Adjustment117
- Throttle Cable Installation119
- Connecting the Electrical Components120
- Electrical Connections120
- Engine Harness Connections120
- Continuity Wire Connection121
- Quick-Connect Mercathode System Connection121
- Battery Connection123
- Installing the Sterndrive Unit123
- Trim Position Sender Connections123
- Troubleshooting Shift Problems123
- Wire Color Code Abbreviations123
- Power Trim System124
- Boat Harness Connector to Engine125
- Boat Harness Installation Guidelines-MPI Sterndrive125
- Key Switch Connector125
- Trim Switch126
- Accessory Relay Connection127
- Additional Relay Kit127
- Lanyard Stop Switch127
- Neutral Safety Switch127
- Optional E-Stop127
- Warning Horn127
- CAN P (CAN 1) Connections128
- General Repower Information128
- Transom Ground Connection129
- Transom Harness-Dts/Mechanical Shift129
- Bravo Sterndrive Shift Check (Engine Running)130
- Engine Installation and Initial Engine Alignment-Towsport, Inboard131
- Engine Mount Preadjustment131
- Models with 8 Degree Down-Angle Transmissions134
- Models with V-Drive Transmissions134
- Final Engine Alignment-Towsport, Inboard135
- Exhaust System Guidelines-Towsport137
- Exhaust System Guidelines-Inboard Models138
- Exhaust Hose Connections-Inboard139
- General Information140
- Measuring Exhaust Elbow Height-Towsport140
- Boat Requirements141
- Loading Requirements142
- Loading the Boat (Boats with a Capacity Plate)142
- Loading the Boat (Boats Without a Capacity Plate)144
- Clear Hose Measurement Method146
- Audio Warning Temperature Switch Installation-Inboard147
- Electrical Connections-Towsport, Inboard147
- Boat Harness and Instrumentation Connections-Inboard148
- Audio Warning System Connections-Towsport, Inboard149
- Smartcraft Product149
- Service Engine Light and OBD-M MIL Kit150
- Testing the OBD-M Malfunction Indicator Lamp (MIL)150
- Battery Cables Connection151
- Propeller Selection151
- Shaft Log Seal Connection151
- 6.2L Maximum RPM Specification152
- Adaptive Speed Control (ASC) Propping with G3152
- Boat-In-The-Water Tests152
- Engine Idle Speed152
- Wide-Open Throttle Propping Without G3 Test154
- Checking Shift Operation155
Engine Mechanical 3157
- Engine Block Codes158
- Identification158
- Kent-Moore159
- Tools159
- Precautions160
- External Engine Components161
- Torque Specifications161
- Crankcase Oil Dipstick Measurements162
- Engine Rotation162
- General Information162
- Repair Guidelines162
- Front Mounts163
- Rear Mounts163
- Sterndrive Engine Mounts163
- Cylinder Head and Rocker Cover Components164
- Engine Components164
- Timing Chain and Front Cover Components166
- Crankshaft and Camshaft168
- Piston and Connecting Rod170
- Intake Manifold and Fuel Rail (MPI)172
- Oil Pan and Oil Pump174
- Remote Oil Filter176
- Removal178
- Rocker Arm Cover178
- Rocker Arms and Valve Pushrods178
- Finding Top Dead Center (TDC)179
- Method 1179
- Method 2179
- Intake Manifold Assembly180
- Removal180
- Exploded View181
- Hydraulic Valve Lifters181
- Removal181
- Special Information181
- Oil Pump Drive182
- Removal182
- Flywheel and Housing183
- Flywheel Housing Removal183
- Flywheel Removal183
- Oil Pan184
- Removal184
- Front Engine Cover185
- Removal185
- Removal187
- Timing Chain and Sprockets187
- Camshaft188
- Removal188
- Cylinder Head189
- Removal189
- Valve Spring Assembly Exploded View190
- Valve Spring Assembly Removal191
- Connecting Rod, Bearings, and Piston Assembly192
- Exploded View192
- Removal192
- Disassembly193
- Rear Oil Seal194
- Removal194
- Disassembly195
- Oil Pump195
- Removal195
- Crankshaft, Main Bearings, and Engine Block196
- Exploded View196
- Removal196
- Engine Block198
Engine Mechanical 3203
- General Specifications204
- Cylinder Bore205
- Engine Specifications205
- Oil Pump205
- Piston Bore Clearance205
- Piston Rings205
- Connecting Rod206
- Crankshaft206
- Piston Pin206
- Valve206
- Camshaft208
- Clean and Inspect208
- Flywheel208
- Timing Chain208
- Cylinder Reconditioning209
- Cylinder Boring210
- Cylinder Honing210
- Piston Selection210
- Camshaft Bearings211
- Engine Block Plugs214
- Cleaning216
- Crankshaft and Pistons216
- Main Bearing Inspection217
- Crankshaft Installation219
- Main Bearing Clearance, Plastigauge Method222
- Crankshaft End Play223
- Piston Inspection224
- Preliminary Inspection224
- Assembly226
- Piston Ring Gap Inspection226
- Piston and Rod Installation227
- Piston/Connecting Rod Assembly227
- Connecting Rod Bearing Clearance, Micrometer Method231
- Connecting Rod Bearing Clearance, Plastigauge Method232
- Inspection234
- Installation234
- Oil Pump234
- Camshaft235
- Inspection235
- Installation236
- Assembly237
- Inspection237
- Timing Chain237
- Checking Timing Chain Deflection238
- Crankcase Front Cover239
- Installation239
- Rear Seal Installation240
- Inspection241
- Oil Pan241
- Installation242
- Core Plug Installation245
- Cylinder Head245
- Inspection246
- Repair249
- Cylinder Head Reassembly251
- Installation253
- Inspection256
- Lifters256
- Inspection257
- Installation257
- Lifter Installation257
- Oil Pump Drive257
- Inspection258
- Rocker Arms and Pushrods258
- Installation259
- Installation261
- Intake Manifold261
- Intake Manifold Assembly261
- Cleaning and Inspection264
- Flywheel264
- Installation264
- Rocker Arm Cover264
- Cleaning267
- Flywheel Housing267
- Inspection267
- Installation267
- Oil Lines268
- Crankcase Front Cover Oil Seal (Without Removing Front Cover)269
- Installation269
- Removal269
- Installation270
- Main Bearings, Without Crankshaft Removed270
- Valve Spring Assembly Exploded View271
- Valve Spring Assembly Removal271
- Valves and Seals (Without Removing Head)271
Engine Mechanical 3273
- Troubleshooting with a Vacuum Gauge274
- Vacuum Gauge Troubleshooting Guide274
- Measuring Vacuum275
- Mechanical Engine Noise275
- Normal Condition276
- Used Spark Plug Analysis276
- Chipped Insulator277
- Cold Fouling277
- Wet Fouling (Oil Deposits)277
- High Speed Glazing278
- Overheating278
- Scavenger Deposits278
- Preignition Damage279
- Reversed Coil Polarity279
- Splashed Deposits279
- Mechanical Damage280
- Piston Inspection280
- Starter Motor will Not Crank Engine, or Cranks Slowly281
- Engine Overheat282
- Engine Runs Rough, Misses, or Backfires282
- Engine will Not Start or Is Hard to Start282
- Poor Performance282
- Important Information283
- Low Engine Oil Pressure283
- Low Engine Temperature283
- Water in the Engine283
- Compression Gauge Testing284
- Leak-Down Testing284
Electrical System295
- Precautions296
- Starter Specifications297
- Wire Color Code Abbreviations297
- Starter Motor Exploded View298
- Starter Motor Circuit300
- Starter Solenoid Circuit300
- Starting System Electrical Diagrams300
- Battery Cables for Mercruiser Models301
- Starter Relay301
- Starting Circuit Overload Protection301
- Hot Stud302
- Inspection302
- Starter302
- Starter Removal303
- Starter Solenoid303
- Water and Corrosion Inspection303
- Starter Installation304
- Low Voltage Tests305
- Starting System Tests305
- Voltage Drop Test306
Electrical System307
- Precautions308
- Ignition Components309
- Waste Spark System Specifications309
- Inspection310
- Installation310
- Removal310
- Spark Plug Removal, Inspection, and Installation310
- Spark Plug Wires310
- Wire Color Code Abbreviations310
- Ignition Coil311
- Ignition Coil Voltage Test311
- Ignition Coil Resistance Test312
- Removal312
- Installation313
Electrical System315
- Precautions316
- Specifications316
- Alternator and Brackets Exploded View318
- Alternator Removal320
- Periodic Maintenance320
- Alternator Installation321
- Serpentine Drive Belt321
- Sterndrive Models322
- Replacing323
- Before You Begin324
- Charging Output Tests324
- Troubleshooting324
- Voltage Drop Test (Alternator Circuit)325
- Sensing and Excitation Circuits326
- Battery will Not Recharge327
- Battery Isolator Diagrams328
Electrical System331
- General Information332
- Precautions332
- Analog Gauges333
- Cleaning the Gauges333
- Configuring the PCM Tachometer Signal (Non-DTS)333
- Gauge Lighting Options333
- Installation333
- Removal333
- Analog Gauge Testing334
- Oil Pressure, Fuel Level, and Coolant Temperature Gauges334
- Battery or Voltage Gauge335
- Cruiselog (Engine Hour Meter)335
- Smartcraft Instrumentation336
- Speedometer336
- Tachometer336
- Boat Harnesses and Installation Connections337
- Boat Wiring337
- CAN Bus Overview337
- Engine Harness and Accessory Power Supply337
- Termination Resistors337
- Boat Harness Installation Guidelines-MPI Sterndrive338
- Service Engine Light and OBD-M MIL Kit344
- System Link Gauge Connections344
- System Link Gauge Extension Harness Installation344
- System Link Gauges344
- Warning System344
- Audio Warning System345
- Guardian Strategy346
- Transom Harness-MPI346
- Wiring Diagrams346
- Helm Mechanical350
- Analog Gauge Harness352
- Mercruiser Remote Control Only to the Harness Assembly (Control Harness Assembly)353
- Power Trim System with a Mercruiser Remote Control354
- Power Trim System with an Outboard Remote Control355
- 14-Pin Engine Harness Connector356
- Axius Helm Installation (if Equipped)356
- Configuring the PCM Using the CDS356
- DTS Information and Installation356
- Installation Guidelines for DTS System Components356
- Special Tools - DTS Installation356
- DTS Battery Specifications357
- Weather Caps357
- Junction Box (if Equipped)358
Electrical System359
- Engine Control and Sensor Locations360
- Front View360
- Rear View361
- Port Side View362
- PCM 112 Controller363
- PCM Removal and Installation363
- Propulsion Control Module (PCM)363
- 50-Amp Main Circuit Breaker365
- Electrical System Overload Protection365
- Fuses366
- Transom Harness368
- Transom Harness Wiring Diagram (Sterndrive)368
- Wire Color Code Abbreviations370
Fuel System371
- Precautions372
- Fuel Pressure Specifications373
- Fuel Ratings373
- Fuel Requirements373
- Using Reformulated (Oxygenated) Gasoline (USA Only)373
- Alternate Priming Procedure for Fuel System374
- Fabricating a Pressure-Relief Collection Tool374
- Gasoline Containing Alcohol374
- Priming the Fuel System374
- Priming the Fuel System376
- Important Information377
- Low Permeation Fuel Lines377
- Exploded Views378
- Fuel Rail Exploded View378
- Fuel Supply Connections378
- Fuel System Module379
- Throttle Body379
- Anti-Siphon Valve380
- FSM Removal380
- Fuel Delivery System380
- Fuel Supply Module (FSM)380
- Fuel System380
- FSM Disassembly381
- FSM Assembly385
- Throttle Body392
- Throttle Body Cleaning and Inspection392
- Throttle Body Removal392
- Fuel Rail393
- Removal393
- Throttle Body Installation393
- Installation397
- Fuel Injector Wiring Diagram399
- Fuel Rail Pressure Damper399
- Wire Color Code Abbreviations399
- Fuel Pressure Gauge Setup and Use400
- Troubleshooting400
- Checking for Restrictions/Vapor Lock Problems in Fuel Delivery Systems401
- Equipment Used to Test Fuel RVP, Fuel Temperature, or Fuel System Vacuum402
Cooling System405
- General Cooling System Information406
- Seawater Inlet Hose406
- Seawater Inlet Specifications406
- Seawater Pump Output Test407
- Water Heater Installation407
- Return Hose Connection408
- Supply Hose Connection408
- Seawater Pump (if Equipped)409
- Seawater Pump Replacement409
- Seawater Pump-Exploded View409
- Seawater Pump Disassembly410
- Cleaning and Inspection411
- Seawater Pump Assembly411
- Removal413
- Water Circulating Pump413
- Cleaning and Inspection414
- Installation414
- Air Manifold and Air Pump-Exploded View415
- Air-Actuated Drain System415
- General Information415
- Testing415
- Air Manifold416
- Drain Check Valve416
- General Information416
- Exploded View417
- Inspection and Cleaning417
- Poppet Valve418
- Poppet Valve Assembly-Exploded View418
- Poppet Valve Operation418
- Poppet Valve Replacement419
- Cleaning and Inspection420
- Removal420
- Water Distribution Housing420
- Water Distribution Housing Installation420
Cooling System429
- Specifications430
- Heat Exchanger Assembly-Exploded View431
- Bravo Models with Closed Cooling432
- Crossover for Closed Cooling-Exploded View432
- Description432
- Meeting the Minimum Seawater Flow Specifications432
- Installing the Y-Fitting433
- Installing the Seawater Supply Hose434
- Through-The-Hull Seawater Pickup System434
- Seawater Pickup435
- Seawater Strainer435
- Seacock436
- Seawater Strainer437
- Seawater Strainer Installation437
- Seawater Strainer Mounting Requirements437
- Cleaning the Seawater Strainer, if Equipped438
- Coolant438
- Coolant Recommendations438
- Maintaining Coolant Level439
- Pressure Cap Maintenance and Testing439
- Pressure Testing the System440
- Testing Coolant for Alkalinity440
- Testing the Closed-Cooling System440
- Seawater Pressure Test441
- Testing for a Cylinder Head Gasket Leak442
- Thermostat442
- Thermostat Removal442
- Thermostat Testing442
- Changing Coolant443
- Closed-Cooling Section443
- Draining the Closed Cooling System443
- Thermostat Installation443
- Cleaning the Cooling System444
- Filling the Cooling System444
- Blockage445
- Heat Exchanger Assembly445
- Heat Exchanger Removal445
- Testing-Internal Leaks445
- Cleaning and Inspection446
- Heat Exchanger Disassembly446
- Heat Exchanger Repair446
- Heat Exchanger Installation447
Cooling System449
- Bravo with Air-Actuated Drain450
- Models with Standard Cooling450
- Models with Closed Cooling452
- Seawater Circuit (All Models with Closed Cooling)452
- Glycol Circuit Towsport V-Drive454
- Glycol Circuit Inboard V-Drive456
- Glycol Circuit Inboard In-Line458
- Glycol Circuit Towsport Reverse V-Drive460
Exhaust System463
- Determining Catalyst Health464
- Exhaust System Connections464
- Exhaust System Notice464
- Preventing Contamination of the Emissions Control System464
- General Information465
- Measuring Engine Exhaust Elbow Height465
- Loading Requirements466
- Loading the Boat (Boats with a Capacity Plate)466
- Loading the Boat (Boats Without a Capacity Plate)468
- Clear Hose Measurement Method470
- Clear Hose Measurement Method from Seacock or Muffler Drain471
Exhaust System475
- Elbow-To-Manifold Gaskets476
- Exhaust Manifold and Elbow Exploded View478
- Exhaust Elbow Removal481
- Exhaust Elbows481
- Intermediate Exhaust Elbow Kit481
- Exhaust Elbow Installation482
- Exhaust Manifold Removal484
- Exhaust Manifolds484
- Exhaust Manifold Installation486
- Manifold Cleaning and Inspection486
- Oxygen Sensor489
- Exhaust Manifold Coolant Temperature (EMCT) Sensor490
- Installation490
- Removal490
Exhaust System491
- Exhaust System Components492
- 6.2L Exhaust494
- Hose Clamp Identification494
- Tridon® Hose Clamp494
- 6.2L MIE Exhaust Installation495
- Switchable Exhaust495
- General Information497
- Towsport Exhaust497
- Component Replacement498
- Exhaust Angle Measurement498
- Through-The-Propeller Exhaust498
Steering Systems501
- Power-Assisted Steering Components Exploded View504
- Hydraulic Diagrams506
- Neutral506
- Left Turn508
- Right Turn510
- Axius Steering Cylinder Clearance511
- Control Valve511
- Description511
- Power-Assisted Steering Pump512
- Power-Assisted Steering Pump Pulley512
- Power-Assisted Steering Pump Pulley-Removal512
- Power-Assisted Steering Pump Pulley-Installation513
- Power-Assisted Steering Pump Assembly514
- Steering Pump Assembly Removal514
- Steering Pump Assembly Installation515
- Filling and Bleeding516
- Power-Assisted Steering Fluid516
- Replacing the Belt and Adjusting Tension516
- Power Steering Fluid517
- High-Pressure Hose (Pump to Control Valve)518
- Power-Assisted Steering Hoses518
- Return Hose (Pump Reservoir to Fluid Cooler)520
- Return Hose (Control Valve to Fluid Cooler)521
- Power-Assisted Steering System Pressure Test522
- Power-Assisted Steering System Tests522
- Pump Pressure Test524
Steering Systems527
- Approved Hydraulic Steering Fluids528
- Important Information about Through-The-Transom Exhaust528
- Installing the Steering Cylinder528
- Introduction528
- Initial Filling530
- Purging the Hydraulic Steering System530
- Checking Fluid Level531
- Checking Fluid Level after the Initial Fill531
- Engine Warm531
- Engine Cold532
- Connecting the Clevis533
- Steering Circuit Component Diagram533
- Connecting the Hydraulic Hoses to the Tilt Steering Helm534
- Hydraulic Fluid Level535
- Maintaining Fluid Level535
- Setting Fluid Level535
- System Check535
- Important Information536
- Maintenance536
- Troubleshooting Chart536
- Troubleshooting Guide536
Transmissions539
- Identification540
- Specifications540
- 45Iv542
- Transmission and Related Parts542
- 45C DTS and 45C Mechanical543
- 45C and 63 In-Line Transmissions544
- 63A Dts544
- Engine544
- Important Information544
- Precautions544
- Propeller544
- Transmission and Propeller Rotation544
- Transmission Fluid545
- 63A Down-Angle and 63IV V-Drive Transmissions548
- Transmission Fluid548
- Transmission Removal551
- Transmission Installation552
- Shift Cable Installation554
- Shift Cable Installation and Adjustment554
- Pressure Test555

Mercury MERCRUISER - Front Mounts; Rear Mounts; Sterndrive Engine Mounts

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