ABYC Diesel Exam Practice Questions And
Correct Answers
A customer complains about decreased performance and higher fuel
consumption. What is the proper sequence of tests a technician might
consider for a mechanically fuel-injected engine? - -Gather boat history
Visually inspect boat condition and water line
No load RPM
Boost test
Compression Test
- a customer complains of white smoke only when the engine is cold.
Technician A says that this could be caused by a faulty pre-heat device.
Technician B says that the white smoke is caused by partially vaporized
fuel. Who is right? - -Both technicians are correct
- A customer complains the engine idle is rough. Technician A says air in
the fuel system may be the cause. Technician B says the fuel shut-off
solenoid is not operating. Who is correct? - -Technician A
- A leak in piping connections between the turbocharger and engine
intake manifold could cause the engine to - -Emit dark and black exhaust
- A ruptured oil cooler core mat result in - -water in the oil system
or
oil in the water system
- a technician determines a history of excessive water contaminated
fuel. the operator has been using a variety of fuel sources. the LEAST
likely cause is - -the fuel source is contaminated
- a technician is hearing a medium frequency rattle with the engine in
neutral located at the flywheel end of the engine. What is a possible
cause? - -damaged flywheel flex-plate
- According to ABYC standard H-33, in diesel fuel systems with multiple
engines and/or multiple tanks - -fueling valves must be labeled as to
function and position
- According to ABYC standards, what is the minimum bend radius of a
control cable? - -Manufacturer's recommended minimum
- after severely overheating his engine and making the required repairs
the customer complains of excessive coolant usage. your test show that
, during normal running the engine does NOT overheat, but coolant is
pushing out through the over flow tube of the expansion tank. what would
most likely NOT be the cause? - -raw water pump impeller
- an indication of alternator output can be obtained by - -comparing
battery voltage with engine running and not running
- At high speed the raw water pressure shows heavy fluctuation as
indicated on a pressure gauge. A possible cause would be: - -Clogged
exhaust riser
- Black soot around the engine compartment openings might indicate: -
-Insufficient engine room ventilation
- compared to gasoline, diesel fuel is more susceptible to - -microbe
contamination
- conductance battery testing may require input - -CCA or MCA`
- Coolant conditioner filters should be replaced: - -According to
manufacturers specification
- Diesel exhaust systems produce small amounts of a dangerous gas,
the gas is: - -Carbon Monoxide
- during a sea trial with mechanical governor engines too find the port
engine will not come up to full load, your notes show the high idle on the
port engine was 300 rpm below specs. the most likely answer is - -throttle
linkage adjustment
- During operation of the boat the technician notes an oil slick at the
exhaust outlet. This most likely indicates - -There is a leak in the raw
water cooler
- excessive black exhaust smoke is an indication of - -excessive load or
over fueling
- Exhaust gases leaking into the coolant system may be caused by a
defective - -Cylinder-head Gasket
- Following a recent reposer, the owner complains of overheating at high
speed. Technician A says that the thermostats are most likely the problem.
Technician B says that the seawater intake system should be checked
against the MFG specifications, who is correct? - -Technician B
- If the electric starter will not crank the engine, the problem may be
caused by - -a run-down battery
a defective starter
internal engine problems
Correct Answers
A customer complains about decreased performance and higher fuel
consumption. What is the proper sequence of tests a technician might
consider for a mechanically fuel-injected engine? - -Gather boat history
Visually inspect boat condition and water line
No load RPM
Boost test
Compression Test
- a customer complains of white smoke only when the engine is cold.
Technician A says that this could be caused by a faulty pre-heat device.
Technician B says that the white smoke is caused by partially vaporized
fuel. Who is right? - -Both technicians are correct
- A customer complains the engine idle is rough. Technician A says air in
the fuel system may be the cause. Technician B says the fuel shut-off
solenoid is not operating. Who is correct? - -Technician A
- A leak in piping connections between the turbocharger and engine
intake manifold could cause the engine to - -Emit dark and black exhaust
- A ruptured oil cooler core mat result in - -water in the oil system
or
oil in the water system
- a technician determines a history of excessive water contaminated
fuel. the operator has been using a variety of fuel sources. the LEAST
likely cause is - -the fuel source is contaminated
- a technician is hearing a medium frequency rattle with the engine in
neutral located at the flywheel end of the engine. What is a possible
cause? - -damaged flywheel flex-plate
- According to ABYC standard H-33, in diesel fuel systems with multiple
engines and/or multiple tanks - -fueling valves must be labeled as to
function and position
- According to ABYC standards, what is the minimum bend radius of a
control cable? - -Manufacturer's recommended minimum
- after severely overheating his engine and making the required repairs
the customer complains of excessive coolant usage. your test show that
, during normal running the engine does NOT overheat, but coolant is
pushing out through the over flow tube of the expansion tank. what would
most likely NOT be the cause? - -raw water pump impeller
- an indication of alternator output can be obtained by - -comparing
battery voltage with engine running and not running
- At high speed the raw water pressure shows heavy fluctuation as
indicated on a pressure gauge. A possible cause would be: - -Clogged
exhaust riser
- Black soot around the engine compartment openings might indicate: -
-Insufficient engine room ventilation
- compared to gasoline, diesel fuel is more susceptible to - -microbe
contamination
- conductance battery testing may require input - -CCA or MCA`
- Coolant conditioner filters should be replaced: - -According to
manufacturers specification
- Diesel exhaust systems produce small amounts of a dangerous gas,
the gas is: - -Carbon Monoxide
- during a sea trial with mechanical governor engines too find the port
engine will not come up to full load, your notes show the high idle on the
port engine was 300 rpm below specs. the most likely answer is - -throttle
linkage adjustment
- During operation of the boat the technician notes an oil slick at the
exhaust outlet. This most likely indicates - -There is a leak in the raw
water cooler
- excessive black exhaust smoke is an indication of - -excessive load or
over fueling
- Exhaust gases leaking into the coolant system may be caused by a
defective - -Cylinder-head Gasket
- Following a recent reposer, the owner complains of overheating at high
speed. Technician A says that the thermostats are most likely the problem.
Technician B says that the seawater intake system should be checked
against the MFG specifications, who is correct? - -Technician B
- If the electric starter will not crank the engine, the problem may be
caused by - -a run-down battery
a defective starter
internal engine problems
