Troubleshooting; Starter Motor Will Not Crank The Engine (Electric Start Models); Engine Will Not Start; Engine Runs Erratically - Mercury 40 Sea Pro User Manual

Starter Motor Will Not Crank The Engine (Electric Start Models)

POSSIBLE CAUSES
• Remote control models - Blown 20 Amp fuse in the starting circuit. Refer to Maintenance section.
• Outboard is not shifted to neutral position.
• Weak battery or battery connections are loose or corroded.
• Ignition key switch failure.
• Wiring or electrical connection faulty.
• Starter motor or starter solenoid failure.

Engine Will Not Start

POSSIBLE CAUSES
• Lanyard stop switch not in "RUN" position.
• Incorrect starting procedure. Refer to Operation section.
• Old or contaminated gasoline.
• Engine flooded. Refer to Operation section.
• Fuel is not reaching the engine.
a. Fuel tank is empty.
b. Fuel tank vent not open or restricted.
c. Fuel line is disconnected or kinked.
d. Primer bulb not squeezed.
e. Primer bulb check valve is faulty.
f. Fuel filter is obstructed. Refer to Maintenance section.
g. Fuel pump failure.
h. Fuel tank filter obstructed.
• Ignition system component failure.
• Spark plugs fouled or defective. Refer to Maintenance section.

Engine Runs Erratically

POSSIBLE CAUSES
• Spark plugs fouled or defective. Refer to Maintenance section.
• Incorrect setup and adjustments.
• Fuel is being restricted to the engine.
• Engine fuel filter is obstructed. Refer to Maintenance section.
• Fuel tank filter obstructed.
• Stuck anti-siphon valve on built in fuel tank.
• Fuel line is kinked or pinched.
• Fuel pump failure.
• Ignition system component failure.

Performance Loss

POSSIBLE CAUSES
• Throttle not fully open.
• Damaged or improper size propeller.
• Incorrect engine timing, adjustments, or setup.
• Boat overloaded or load improperly distributed.

TROUBLESHOOTING

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