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

Mercury Outboard 40 HP (1972 - 1989)

  • Includes online edition!
  • What's Included

    Use the online manual straight away
    Print book ships same day (before 3pm)
    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

    Print book ships same day (before 3pm)
    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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This Mercury manual is 368 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 / Propellers / 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 / Phase-maker ignition troubleshooting / Thunderbolt flywheel CD ignition troubleshooting / Fuel system / Engine

CHAPTER FOUR / LUBRICATION, MAINTENANCE AND TUNE-UP
Model changes and redesignation / Lubrication / Fuel selection / Gasahol / Recommended fuel mixture / Fuel mixing procedures / AutoBlend oil injection / Lower drive unit lubrication / Salt water corrosion of gear housing bearing carrier and nut / Winter storage / Anti-corrosion maintenance / Complete submersion / Engine flushing / Tune-up / Compression test / Spark plugs / Lower unit and water pump check / Fuel system service / Fuel line service / Fuel filter service / Fuel pump / Ignition service / Maker-Point ignition / Battery, Starter and solenoid (electric start models only) / Timing, synchronization and adjustment / On-boat performance test / Specifications

CHAPTER FIVE / TIMING, SYNCHRONIZATION AND ADJUSTING
Engine timing / Synchronizing / Required equipment / Mercury 3.5 and 3.6 hp / Mercury 40 and 2-cylinder 4 hp with Thunderbolt breakerless ignition / Mercury 45, 4.5 and 4 (1986-1987) / Merc model 40, 75, and 110 with Phase-maker ignition / Merc 4 and 5 hp (1988-on) / Merc model 75 and 7.5 hp (through serial No. 5226934); Merc model 110 and 9.8 hp (through serial No. 5206549) / Mercury 7.5 hp (above serial No. 5226934); Mercury 9.8 hp (above serial No. 5206549) / Mercury 6, 8, 9.9 and 15 hp / Mercury 18 and 25 hp (1979-1984) / Mercury 18, 20 and 25 hp (with WMC carburetor) / Mercury 200 with Phase-maker ignition / Merc model 200 and 20 hp (1979-1980) with Thunderbolt breakerless ignition / Merc model 402, 35 and 40 hp / Specifications

CHAPTER SIX / FUEL SYSTEM
Fuel pump / Carburetors / Integral fuel pump carburetor (original design) / Integral fuel pump carburetor (1979-1985 Merc 18 and 25 hp) / Centerbowl carburetor (Merc 4 hp 2-cylinder model) / Sidebowl carburetor / 3.5 and 3.6 hp carburetor / Integral fuel pump carburetor (with primer system) / Integral fuel pump carburetor (1988-on Merc 4 and 5 hp) / Sight bowl fuel filter / Anti-siphon devices / Fuel tank / Fuel line and primer bulb / Specifications

CHAPTER SEVEN / IGNITION AND ELECTRICAL SYSTEMS
Battery / Battery charging system / Electric starting system / Ignition system / Thunderbolt Phase-maker CD ignition system / Thunderbolt CD breakerless ignition system / Specifications

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

CHAPTER NINE / LOWER UNIT
Service precautions / Gear housing / Water pump / Bearing carrier and propeller shaft / Pinion gear, drive shaft and forward gear / Shift shaft, bushing and cam / Pinion depth/gear backlash / Propeller / Specifications

CHAPTER TEN / AUTOMATIC REWIND STARTERS
Merc 3.5 and 3.6 hp / Merc 4 and 5 hp (1988-on) / Merc 6, 8, 9.9, 15, 18, 20 (1986-on) and 25 hp / Merc 2-cylinder 4 hp / Merc 4.5, 45, 7.5, 75, 9.8, 110, 200, 20 (1979-1980), 402, 35 and 40 / Shift interlock adjustment / Specifications

CHAPTER ELEVEN / MERC THRUSTER ELECTRIC OUTBOARDS
Lubrication / Periodic maintenance / Battery / Propeller / Electrical troubleshooting / Electrical component testing (variable speed control models) / Electrical component testing rotary switch models / Lower unit / Control housing / Specifications

INDEX

WIRING DIAGRAMS

Models covered:
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 3.5
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 3.6
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 4 (40)
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 4.5 (45)
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 5
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 6
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 7.5 (75)
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 8
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 9.8 (110)
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 9.9
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 15
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 18
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 20 (200)
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 25
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 35
1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 Mercury Merc 40 (402)

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Mercury Merc 3.5 (1972-1989)
Mercury Merc 3.6 (1972-1989)
Mercury Merc 4 (40) (1972-1989)
Mercury Merc 4.5 (45) (1972-1989)
Mercury Merc 5 (1972-1989)
Mercury Merc 6 (1972-1989)
Mercury Merc 7.5 (75) (1972-1989)
Mercury Merc 8 (1972-1989)
Mercury Merc 9.8 (110) (1972-1989)
Mercury Merc 9.9 (1972-1989)
Mercury Merc 15 (1972-1989)
Mercury Merc 18 (1972-1989)
Mercury Merc 20 (200) (1972-1989)
Mercury Merc 25 (1972-1989)
Mercury Merc 35 (1972-1989)
Mercury Merc 40 (402) (1972-1989)

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