1969 Evinrude 40 HP Big Twin, Big Twin Electric Lark Service Manual 4596, Page 16Get this manual
TROUBLE CHECK CHART (CONT) TROUBLE POSSIBLE CAUSE ASPARK PLUGSSee Section Crossed or reversed eads Cover or inner terminal damaged (spark plug point out of H.Tlead) Faulty leads Loose, low torque Incorrect heat range Defective (cracked insulator) BMAGNETOSee Section Incorrectly ad justed pOints Loose wiring Coil or condenser damaged (loose) Fibre breaker block worn Points dirty or pitted
3MOTOR MISFIRES (Assuming Fuel SystemCarburetor OK)
4POOR PERFORMANCE ON BOAT
AINCORRECT PROPELLER Incorrect tilt angle (smoking) Poor fuel mixtoo much oil(smoking) Remote controls incorrectly adjusted Propeller hub slipping Bent or worn propeller Exhaust outlet damaged or missing Bent gear housing or exhaust housing (broken driveshafts) Altitude horsepower loss Catamaran (single engine)venturi effect Exhaust leaks Overheating BCAVITATION Protruding hull attachments Keel too long Bent propeller (vibration) Transom too high CBOAT Improper load distribution Marine growth on bottom Added weight (water absorption) Hook in bottom ACONTROL BOX AND ELECTRICAL CONNECTIONS See Section Control box andor power head connections not coupled or corroded Faulty activating switch in remote control box Open circuit (broken wires) (ignition switch) BLOWER UNITSee Section Incorrect lubricant (Type "C" only) Loose clutch spring screws Dam aged coil, worn clutch spring, or hub Burned shift cable ACHARGING CIRCUITSee Section Shorted or open windingsarmature or field Regulator damaged Generator PolarityReversed