1976 Johnson 4HP 4R76, 4W76 Outboards Service Manual, Page 14Get this manual
TROUBLE
POSSIBLE CAUSE BMAGNETOSee Section Incorrectly adjusted points Loose wiring Coil or condenser damaged (loose) Fibre breaker block worn Points dirty or pitted Defective breaker cam Loose armature plate screws or worn bushing AMOTOR ADJUSTMENT Incorrect tilt angle BCAVITATION Protruding hull attachments Keel too long Transom too high CBOAT Improper load distribution Marine growth on bottom Added weight (water absorption) Hook in bottom Mis-matched boat and motor (boat underpowered)
3MOTOR MISFIRES (Assuming
Fuel SystemCarburetor OK) (Cont)
4 POOR PERFORMANCE ON BOAT (Assuming Motor Runs OK)
SUBMERGED MOTORS
If motor is lost overboard while running, it should always be disas-
sembled before any attempt is made to start itOften internal parts are damaged, and attempts at starting or running under these conditions can result in further damageA motor lost overboard in salt water should always be disassembled and cleaned before starting is attemptedSome materials used in modern engines are subject to very rapid corrosion in the presence of salt water and should be inspected to determine if replacements are requiredA motor lost overboard in fresh water can usually be safely started if recovered within twelve hours providing no sand or silt is presentRemove the spark plugs, the carburetor orifice screw, and drain all fuel lines and tank Craqk the engine with starter rope until all water present has been expelledSquirt outboard lubricant into spark plug holesReassemble and startIf sand has entered the engine, no attempt at starting should be madeIf it is impossible to have the engine serviced immediately after it has