Clymer B721 Manuals & Subscriptions
Mercury 3.5 - 40 HP Outboards (Includes Electric Motors), 1972-1989Part #: B721
368 pages CHAPTER ONE / GENERAL INFORMATIONManual organization / Notes, cautions and warnings / Torque specifications / Engine operation / Fasteners / Lubricants / Gasket sealant / Galvanic corrosion / Protection from galvanic corrosion / Propellers
CHAPTER TWO / TOOLS AND TECHNIQUESSafety first / Basic hand tools / Test equipment / Service hints / Special tips / Mechanic's techniques
CHAPTER THREE / TROUBLESHOOTINGOperating 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-UPModel changes and redesignation / Lubrication / AutoBlend oil injection / Winter storage / Anti-corrosion maintenance / Complete submersion / Engine flushing / Tune-up
CHAPTER FIVE / TIMING, SYNCHRONIZATION AND ADJUSTINGEngine 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
CHAPTER SIX / FUEL SYSTEMFuel 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
CHAPTER SEVEN / IGNITION AND ELECTRICAL SYSTEMSBattery / Battery charging system / Electric starting system / Ignition system / Thunderbolt Phase-maker CD ignition system / Thunderbolt CD breakerless ignition system
CHAPTER EIGHT / POWER HEADEngine serial number / Gaskets and sealants / Power head
CHAPTER NINE / LOWER UNITService 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
CHAPTER TEN / AUTOMATIC REWIND STARTERSMerc 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
CHAPTER ELEVEN / MERC THRUSTER ELECTRIC OUTBOARDSLubrication / Periodic maintenance / Battery / Propeller / Electrical troubleshooting / Electrical component testing (variable speed control models) / Electrical component testing rotary switch models / Lower unit / Control housing
INDEXWIRING DIAGRAMS Models covered: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 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 35
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 40 (402)
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
1972-1989 MERCURY Merc 9.8 (110) 1972-1989 MERCURY Merc 9.9
Manuals: Mercury
Clymer Mercury Manual 3.5-40 hp Outboard B721 1972-89
Normalized SKU: B721
UPC Code: 024185739579