Mercury 3.5-40 HP Outboards (Includes Electric Motors) 1972-1989

Mercury 3.5 - 40 hp outboards (includes electric motors), 1972-1989. Part #: b721. 368 pages. 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. Chapter two / tools and techniques. Safety first / basic hand tools / test equipment / service hints / special tips / mechanic's techniques. 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 / auto blend oil injection / winter storage / anti-corrosion maintenance / complete submersion / engine flushing / tune-up. 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 breaker less 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 number 5226934); merc model 110 and 9.8 hp (through serial number 5206549) / mercury 7.5 hp (above serial number 5226934); mercury 9.8 hp (above serial number 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 breaker less ignition / merc model 402, 35 and 40 hp. Chapter six / fuel system. Fuel pump / carburetors / integral fuel pump carburetor (original design) / integral fuel pump carburetor (1979-1985 merc 18 and 25 hp) / center bowl carburetor (merc 4 hp 2-cylinder model) / side bowl 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 systems. Battery / battery charging system / electric starting system / ignition system / thunderbolt phase-maker cd ignition system / thunderbolt cd breaker less ignition system. Chapter eight / power head. Engine serial number / gaskets and sealants / power head. 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. 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. 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. 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 151972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 mercury merc 181972 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 251972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 mercury merc 3.51972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 mercury merc 3.61972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 mercury merc 351972 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 51972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 mercury merc 61972 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 81972-1989 mercury merc 9.8 (110) 1972-1989 mercury merc 9.9. Manufacturer: clymer.