South Carolina Outboard Motor
Technician Certification License Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. The primary purpose of the anode on an outboard motor is to:
A. Increase engine power output
B. Protect metal components from corrosion
C. Improve fuel efficiency
D. Regulate engine temperature
The anode is a sacrificial metal that corrodes instead of other metal
parts, protecting them from electrolytic corrosion.
2. What type of oil is typically recommended for a four-stroke outboard
engine?
A. 2-cycle oil
B. Marine-rated 4-stroke engine oil
C. Hydraulic oil
D. Automotive weight motor oil
Marine-rated 4-stroke oil is formulated to handle high RPM friction
and saltwater exposure found in outboard engines.
3. Which component converts electrical energy into mechanical energy
to start the engine?
A. Alternator
B. Solenoid
C. Starter motor
D. Voltage regulator
, The starter motor receives electrical power to turn the engine over
and initiate combustion.
4. What does a carburetor do?
A. Filters the air
B. Measures coolant temperature
C. Mixes air and fuel for combustion
D. Controls engine timing
A carburetor creates the correct air/fuel mixture for efficient
combustion in older outboard motors.
5. Which substance should never be used to clean rubber fuel lines?
A. Water
B. Strong solvent
C. Mild detergent
D. Soap and water
Strong solvents degrade rubber lines, leading to swelling, cracks, and
failure.
6. A high-pitch squealing noise from the belt area most likely indicates:
A. Low engine coolant
B. Worn or loose belt
C. Clogged fuel filter
D. Ignition timing issue
Loose or worn belts slip on pulleys, causing squealing noises under
load.
7. What is the function of the thermostat in an outboard cooling system?
A. Cool the oil
B. Increase fuel flow
C. Regulate coolant temperature
D. Control exhaust gas
The thermostat opens and closes to maintain optimal engine
operating temperature.
8. Electrolysis damage in an outboard lower unit is typically caused by:
A. Overheating
B. Electrical current flowing through water
C. Low gear oil
D. Incorrect propeller size
, Stray electrical current in water causes metal to degrade through
electrolysis.
9. The spark plug gap affects:
A. Oil pressure
B. Gear ratio
C. Ignition efficiency
D. Coolant flow
Correct gap ensures proper spark and efficient combustion.
10. When replacing propellers, what factor most affects
performance?
A. Engine color
B. Water temperature
C. Pitch and diameter
D. Number of horseshoe clips
Propeller pitch and diameter directly determine performance
characteristics like acceleration and top speed.
11. A flooded engine condition is commonly caused by:
A. Dead battery
B. Excess fuel in combustion chamber
C. Dirty water pump
D. Fore and aft imbalance
Too much fuel in the cylinder prevents ignition from occurring.
12. Too much carbon buildup on the piston crown can result in:
A. Improved fuel economy
B. Higher compression ratio
C. Engine knocking
D. Lower idle speed
Carbon raises compression and can cause detonation (knocking).
13. What tool is used to test battery specific gravity?
A. Torque wrench
B. Multimeter
C. Hydrometer
D. Compression gauge
A hydrometer measures the density of battery electrolyte to
determine charge state.
Technician Certification License Exam
Practice Questions And Correct Answers
(Verified Answers) Plus Rationale 2026
Q&A| Instant Download Pdf
1. The primary purpose of the anode on an outboard motor is to:
A. Increase engine power output
B. Protect metal components from corrosion
C. Improve fuel efficiency
D. Regulate engine temperature
The anode is a sacrificial metal that corrodes instead of other metal
parts, protecting them from electrolytic corrosion.
2. What type of oil is typically recommended for a four-stroke outboard
engine?
A. 2-cycle oil
B. Marine-rated 4-stroke engine oil
C. Hydraulic oil
D. Automotive weight motor oil
Marine-rated 4-stroke oil is formulated to handle high RPM friction
and saltwater exposure found in outboard engines.
3. Which component converts electrical energy into mechanical energy
to start the engine?
A. Alternator
B. Solenoid
C. Starter motor
D. Voltage regulator
, The starter motor receives electrical power to turn the engine over
and initiate combustion.
4. What does a carburetor do?
A. Filters the air
B. Measures coolant temperature
C. Mixes air and fuel for combustion
D. Controls engine timing
A carburetor creates the correct air/fuel mixture for efficient
combustion in older outboard motors.
5. Which substance should never be used to clean rubber fuel lines?
A. Water
B. Strong solvent
C. Mild detergent
D. Soap and water
Strong solvents degrade rubber lines, leading to swelling, cracks, and
failure.
6. A high-pitch squealing noise from the belt area most likely indicates:
A. Low engine coolant
B. Worn or loose belt
C. Clogged fuel filter
D. Ignition timing issue
Loose or worn belts slip on pulleys, causing squealing noises under
load.
7. What is the function of the thermostat in an outboard cooling system?
A. Cool the oil
B. Increase fuel flow
C. Regulate coolant temperature
D. Control exhaust gas
The thermostat opens and closes to maintain optimal engine
operating temperature.
8. Electrolysis damage in an outboard lower unit is typically caused by:
A. Overheating
B. Electrical current flowing through water
C. Low gear oil
D. Incorrect propeller size
, Stray electrical current in water causes metal to degrade through
electrolysis.
9. The spark plug gap affects:
A. Oil pressure
B. Gear ratio
C. Ignition efficiency
D. Coolant flow
Correct gap ensures proper spark and efficient combustion.
10. When replacing propellers, what factor most affects
performance?
A. Engine color
B. Water temperature
C. Pitch and diameter
D. Number of horseshoe clips
Propeller pitch and diameter directly determine performance
characteristics like acceleration and top speed.
11. A flooded engine condition is commonly caused by:
A. Dead battery
B. Excess fuel in combustion chamber
C. Dirty water pump
D. Fore and aft imbalance
Too much fuel in the cylinder prevents ignition from occurring.
12. Too much carbon buildup on the piston crown can result in:
A. Improved fuel economy
B. Higher compression ratio
C. Engine knocking
D. Lower idle speed
Carbon raises compression and can cause detonation (knocking).
13. What tool is used to test battery specific gravity?
A. Torque wrench
B. Multimeter
C. Hydrometer
D. Compression gauge
A hydrometer measures the density of battery electrolyte to
determine charge state.