ABYC-Marine Engines and Fuel Systems
Certification Exam Questions and Answers
Question 1
Gasoline (Petrol) Fuel Systems
Carbureted Fuel Systems
The fundamental principle of operation for a carburetor is based on the
_______________________.
Correct Answer
Bernoulli principle
Question 2
Principles of Engine Operation
To avoid parallax error when setting base timing, the technician should:
A. Establish a direct line of sight over the centerline of the engine crank shaft pulley
B. Use paint marker or whiteout to brighten the timing marks
C. Close all hatches to reduce ambient light
D. Use an inductive timing light
Correct Answer
A. Establish a direct line of sight over the centerline of the engine crank shaft pulley
Question 3
Diesel Fuel Systems
Diesel Fuel-Injection Systems
An adequate supply of _____________ is key
Correct Answer
combustion air
Page 1 of 303
,Question 4
Engine Electrical Systems
Battery Categories
True or False
Using the Table 6-1 on pg 134 that shows the correlation between open-circuit
voltage and percent of charge in a traditional flooded-cell lead-acid battery.
A flooded-cell battery that shows a Voltage level of 12.2v shows it has a capacity of
75%
Correct Answer
False, a Flooded Cell Battery with a voltage level of 12.2 v has a capacity of 50%
Question 5
Diesel Fuel Systems
Diesel Fuel-Injection Systems
The net result of this is that the engine makers can now deliver more power,
improved fuel economy, and reduced ____________________ due to the precision with
which the systems can manage fuel delivery
Correct Answer
exhaust emissions
Question 6
Engine Cooling Systems
Cooling-System Servicing : Coolant Testing
On ______________ engines, actual chemical analysis of the engine coolant, just like oil
analysis is a common routine.
Correct Answer
larger
Page 2 of 303
,Question 7
Engine Cooling Systems
Troubleshooting Cooling Systems : Air in the Cooling System
The term sometimes used to describe the process of using an infrared heat sensor is
"____________" or temperature differential. Some manuals also describe a "__________"
test, which is just measuring pressure losses in the exhaust hoses.
Correct Answer
Delta T
Delta P
Question 8
Diesel Fuel Systems
Interpreting Exhaust Smoke
Black smoke is always indicative of too much _________ being delivered
Correct Answer
fuel
Question 9
Drive Systems
Sterndrive Care and Maintenance
Fighting with or forcing a drive into place is not only very difficult, it can cause a great
deal of damage to the ________________ on the back of the engine and cause premature
_________________________ wear on the shaft assembly.
Correct Answer
coupler
universal joint
Page 3 of 303
, Question 10
Gasoline (Petrol) Fuel Systems
Fuel-System Maintenance and Troubleshooting : Vapor Lock
Vapor lock is much less likely on fuel injected engines where the fuel pump is
______________________.
Correct Answer
in the tank
Question 11
Diesel Fuel Systems
The most frequent cause of diesel-engine problems is due to:
A. improper air source
B. engine improperly tuned
C. fuel contamination
D. high operating temperature
Correct Answer
C. fuel contamination
Question 12
Engine Electrical Systems
Overcurrent Protection for Starting Circuits
The exception for wires connected directly to a battery terminal, where the 7" rule
can't be met, allows the overcurrent device to be placed up to ____in (1.8 m) away,
along the length of the wire run.
Correct Answer
72 in
Page 4 of 303
Certification Exam Questions and Answers
Question 1
Gasoline (Petrol) Fuel Systems
Carbureted Fuel Systems
The fundamental principle of operation for a carburetor is based on the
_______________________.
Correct Answer
Bernoulli principle
Question 2
Principles of Engine Operation
To avoid parallax error when setting base timing, the technician should:
A. Establish a direct line of sight over the centerline of the engine crank shaft pulley
B. Use paint marker or whiteout to brighten the timing marks
C. Close all hatches to reduce ambient light
D. Use an inductive timing light
Correct Answer
A. Establish a direct line of sight over the centerline of the engine crank shaft pulley
Question 3
Diesel Fuel Systems
Diesel Fuel-Injection Systems
An adequate supply of _____________ is key
Correct Answer
combustion air
Page 1 of 303
,Question 4
Engine Electrical Systems
Battery Categories
True or False
Using the Table 6-1 on pg 134 that shows the correlation between open-circuit
voltage and percent of charge in a traditional flooded-cell lead-acid battery.
A flooded-cell battery that shows a Voltage level of 12.2v shows it has a capacity of
75%
Correct Answer
False, a Flooded Cell Battery with a voltage level of 12.2 v has a capacity of 50%
Question 5
Diesel Fuel Systems
Diesel Fuel-Injection Systems
The net result of this is that the engine makers can now deliver more power,
improved fuel economy, and reduced ____________________ due to the precision with
which the systems can manage fuel delivery
Correct Answer
exhaust emissions
Question 6
Engine Cooling Systems
Cooling-System Servicing : Coolant Testing
On ______________ engines, actual chemical analysis of the engine coolant, just like oil
analysis is a common routine.
Correct Answer
larger
Page 2 of 303
,Question 7
Engine Cooling Systems
Troubleshooting Cooling Systems : Air in the Cooling System
The term sometimes used to describe the process of using an infrared heat sensor is
"____________" or temperature differential. Some manuals also describe a "__________"
test, which is just measuring pressure losses in the exhaust hoses.
Correct Answer
Delta T
Delta P
Question 8
Diesel Fuel Systems
Interpreting Exhaust Smoke
Black smoke is always indicative of too much _________ being delivered
Correct Answer
fuel
Question 9
Drive Systems
Sterndrive Care and Maintenance
Fighting with or forcing a drive into place is not only very difficult, it can cause a great
deal of damage to the ________________ on the back of the engine and cause premature
_________________________ wear on the shaft assembly.
Correct Answer
coupler
universal joint
Page 3 of 303
, Question 10
Gasoline (Petrol) Fuel Systems
Fuel-System Maintenance and Troubleshooting : Vapor Lock
Vapor lock is much less likely on fuel injected engines where the fuel pump is
______________________.
Correct Answer
in the tank
Question 11
Diesel Fuel Systems
The most frequent cause of diesel-engine problems is due to:
A. improper air source
B. engine improperly tuned
C. fuel contamination
D. high operating temperature
Correct Answer
C. fuel contamination
Question 12
Engine Electrical Systems
Overcurrent Protection for Starting Circuits
The exception for wires connected directly to a battery terminal, where the 7" rule
can't be met, allows the overcurrent device to be placed up to ____in (1.8 m) away,
along the length of the wire run.
Correct Answer
72 in
Page 4 of 303
