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The original Haynes Repair Manual - Based on a complete stripdown and rebuild of a vehicle

Mercury Outboard 25 HP (1990 - 1993) Clymer

  • Includes online edition!
  • What's Included

    Use the online manual straight away
    Book ships next working day (before 5pm)
    Fault Finder - Diagnose 400+ problems
    Take on bigger jobs with Haynes’ help
    Wiring diagrams for key vehicle systems
    Extra videos in online manual
    700+ pictures & diagrams of your vehicle
  • Print edition only!
  • What's Included

    Book ships next working day (before 5pm)
    Fault Finder - Diagnose 400+ problems
    Take on bigger jobs with Haynes’ help
    Wiring diagrams for key vehicle systems
    700+ pictures & diagrams of your vehicle
    Suitable for novice and pro mechanics
  • Online edition only!
  • What's Included

    Use the online manual straight away
    Includes ALL content of a printed manual
    Fault Finder - Diagnose 400+ problems
    Take on bigger jobs with Haynes’ help
    Wiring diagrams for key vehicle systems
    Extra videos in online manual
    Print any page at home
    700+ pictures & diagrams of your vehicle

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What's Covered

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This Mercury manual is 640 pages.

QUICK REFERENCE DATA

CHAPTER ONE / GENERAL INFORMATION
Manual organization / Notes, cautions and warnings / Torque specifications / Engine operation / Fasteners / Lubricants / Gasket sealant / Galvanic corrosion / Protection from Galvanic corrosion / Propeller / Specifications

CHAPTER TWO / TOOLS AND TECHNIQUES
Safety first / Basic hand tools / Test equipment / Service hints / Special tips / Mechanic's techniques / Specifications

CHAPTER THREE / TROUBLESHOOTING
Operating requirements / Starting system / Charging system / Ignition system / Breaker-point ignition troubleshooting (1990-1992 3 hp models) / Capacitor discharge ignition (CDI) / Direct voltage tests / Resistance test / Speed limiter / Spark advance/idle stabilizer module troubleshooting / Fuel system / Engine / Specifications

CHAPTER FOUR / LUBRICATION, MAINTENANCE AND TUNE-UP
Lubrication / Proper fuel selection / Recommended fuel mixture / Fuel mixing procedure / AutoBlend II injection system / Constant ratio oil injection / Variable ratio injection system / Lower drive unit lubricant change / Propeller shaft lube / Saltwater corrosion of gear housing bearing carrier and nut / Storage / Anti-corrosion maintenance / Complete submersion / Flushing the cooling system / Tune-up / Compression test / Spark plug plugs / Lower unit and water pump check / Fuel system service / Fuel line and hoses service / Fuel filter service / Fuel pump (all models except fuel-injected models) / Fuel pressure test / Battery and starter check / Starter solenoid check / Alternator and rectifier check / Ignition timing, synchronization and adjustment / On-boat performance test / Specifications

CHAPTER FIVE / TIMING, SYNCHRONIZING AND ADJUSTING
Ignition timing and synchronization / 3 hp models / 3 and 5 hp models / 8, 9.9 and 15 hp models / 20 and 25 hp models / 40 hp models / 50 and 60 hp models (prior to serial No. D000750) / 50 and 60 hp models (serial No. D000750-on) / 75 and 90 hp models / 100 and 115 hp models / 135-200 hp (except EFI) models / 250 and 275 hp models / 150Xri, 175Xri and 200Xri (EFI) models / Specifications

CHAPTER SIX / FUEL SYSTEM
Fuel pump / Carburetors / Throttle plunger carburetor (3 and 3.3 hp models) / Integral fuel pump carburetor (4 and 5 hp models) / Integral fuel pump carburetor (8-25 hp models) / WMA carburetor (40 hp models) / MerCarb center bowl carburetor (50 and 50 hp models prior to serial No. D000750) / WME carburetor (50 and 60 hp serial No. D000750-on, 75, 90, 100 and 115 hp models) / WMH carburetor (135-200 hp models) / MerCarb center bowl carburetor (250 and 275 hp models) / Thermal air valve (135-200 hp models) / Enrichment valve and choke solenoid systems / Anti-siphon devices / Fuel filter / Fuel tank / Fuel hose and primer bulb / Electronic fuel injection (EFI) / Fuel management tests / Specifications

CHAPTER SEVEN / IGNITION AND ELECTRICAL SYSTEMS
Battery / Battery charging system / Starting system / Magneto breaker point ignition / Capacitor discharge ignition (CDI) (1993 3.3 hp models) / Capacitor discharge ignition (CDI) (4-275 hp models) / Specifications

CHAPTER EIGHT / POWER HEAD
Engine serial number / Gaskets and sealants / Fasteners and torque / Power head / Specifications

CHAPTER NINE / LOWER UNIT GEAR HOUSING
Service precautions / Gear housing / Water pump / Bearing carrier and propeller shaft / Pinion gear, drive shaft and forward gear / Lower shift shaft, bushing and cam / Pinion depth/gear backlash / Propeller / Trim tab adjustment / Specifications

CHAPTER TEN / POWER TRIM AND TILT SYSTEM
Manual tilt assist system / One-ram integral power trim system (40-60 hp models) / Three-ram integral power trim system (75-200 hp models) / One-ram oildyne power trim system (250-275 hp models) / Power trim assembly removal/installation / Power trim motor and pump assembly removal/installation / Specifications

CHAPTER ELEVEN / OIL INJECTION SYSTEM
Autoblend II (50 and 60 hp prior to serial No. D000750) / Constant ratio oil injection (40 hp and 50-60 [serial No. D000750-on] hp models) / Injection system service / Variable-ratio oil injection (75-115 hp models) / Warning horn system / Injection system service / Variable-ratio oil injection (V6 models) / Warning hose system / Injection system service / Specifications

CHAPTER TWELVE / MANUAL REWIND STARTERS
3 and 3.3 hp models / 4 and 5 hp models / 8, 9.9, 15, 20 and 25 hp models / 40 hp models / Specifications

INDEX

WIRING DIAGRAMS

Models covered:
1990 1991 1992 1993 Mercury 3 HP
1990 1991 1992 1993 Mercury 3.3 HP
1990 1991 1992 1993 Mercury 4 HP
1990 1991 1992 1993 Mercury 5 HP
1990 1991 1992 1993 Mercury 8 HP
1990 1991 1992 1993 Mercury 9.9 HP
1990 1991 1992 1993 Mercury 15 HP
1990 1991 1992 1993 Mercury 20 HP
1990 1991 1992 1993 Mercury 25 HP
1990 1991 1992 1993 Mercury 40 HP
1990 1991 1992 1993 Mercury 50 HP
1990 1991 1992 1993 Mercury 60 HP
1990 1991 1992 1993 Mercury 75 HP
1990 1991 1992 1993 Mercury 90 HP
1990 1991 1992 1993 Mercury 100 HP
1990 1991 1992 1993 Mercury 115 HP
1990 1991 1992 1993 Mercury 135 HP
1990 1991 1992 1993 Mercury 150 HP
1990 1991 1992 1993 Mercury 150XR4
1990 1991 1992 1993 Mercury 150XR6
1990 1991 1992 1993 Mercury 150XRi
1990 1991 1992 1993 Mercury 175 HP
1990 1991 1992 1993 Mercury 175XRi
1990 1991 1992 1993 Mercury 200 HP
1990 1991 1992 1993 Mercury 200XRi
1990 1991 1992 1993 Mercury 250 HP
1990 1991 1992 1993 Mercury 275 HP

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Clymer Manuals Mercury 175XRi Manual
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Clymer Manuals Mercury 5 HP Online Manual
Clymer Manuals Mercury 8 HP Online Manual
Clymer Manuals Mercury 9.9 HP Online Manual
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Clymer Manuals Mercury 100 HP Online Manual
Clymer Manuals Mercury 115 HP Online Manual
Clymer Manuals Mercury 135 HP Online Manual
Clymer Manuals Mercury 150 HP Online Manual
Clymer Manuals Mercury 150XR4 Online Manual
Clymer Manuals Mercury 150XR6 Online Manual
Clymer Manuals Mercury 150XRi Online Manual
Clymer Manuals Mercury 175 HP Online Manual
Clymer Manuals Mercury 175XRi Online Manual
Clymer Manuals Mercury 200 HP Online Manual
Clymer Manuals Mercury 200XRi Online Manual
Clymer Manuals Mercury 250 HP Online Manual
Clymer Manuals Mercury 275 HP Online Manual

Mercury 3 HP (1990-1993)
Mercury 3.3 HP (1990-1993)
Mercury 4 HP (1990-1993)
Mercury 5 HP (1990-1993)
Mercury 8 HP (1990-1993)
Mercury 9.9 HP (1990-1993)
Mercury 15 HP (1990-1993)
Mercury 20 HP (1990-1993)
Mercury 25 HP (1990-1993)
Mercury 40 HP (1990-1993)
Mercury 50 HP (1990-1993)
Mercury 60 HP (1990-1993)
Mercury 75 HP (1990-1993)
Mercury 90 HP (1990-1993)
Mercury 100 HP (1990-1993)
Mercury 115 HP (1990-1993)
Mercury 135 HP (1990-1993)
Mercury 150 HP (1990-1993)
Mercury 150XR4 (1990-1993)
Mercury 150XR6 (1990-1993)
Mercury 150XRi (1990-1993)
Mercury 175 HP (1990-1993)
Mercury 175XRi (1990-1993)
Mercury 200 HP (1990-1993)
Mercury 200XRi (1990-1993)
Mercury 250 HP (1990-1993)
Mercury 275 HP (1990-1993)

Product Details

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