MDE 4 End of Unit Quiz

MDE 4 End Of Unit Quiz

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3. Damaged or Clogged Charge Air Cooler

Question: What is an economical maintenance routine to address a damaged or clogged charge air cooler?

A) Inspect and clean the charge air cooler, and replace it if necessary

D) Flush the engine cooling system

B) Replace the entire intake manifold

C) Adjust the engine timing

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1. Basic Function of a Turbocharger

Question: What is the primary function of a turbocharger in a main engine?

B) To increase the air intake pressure, allowing more air to enter the engine cylinders

D) To cool the engine by circulating coolant through the cylinder block

C) To reduce the exhaust emissions by filtering out harmful gases

A) To increase the fuel efficiency by injecting more fuel into the cylinders

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Possible Reasons for Reduced Charge Air Cooler Performance

Question: What are possible reasons why the performance of a charge air cooler may be reduced?

A) Accumulation of dirt and debris on the cooler fins

C) A malfunctioning spark plug

D) A blocked fuel filter

B) Excessive engine oil consumption

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Cooling the Air Outlet from the Turbocharger

Question: Why should the air outlet from the turbocharger be cooled before entering the diesel engine cylinder?

B) To lower the temperature of the air, increasing its density and improving combustion efficiency

C) To increase the temperature of the air for better fuel atomization

D) To remove excess moisture from the air to prevent corrosion

A) To reduce the pressure of the air to avoid engine damage

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Purpose of Vent Cocks in Air Coolers

Question: What is the purpose of vent cocks in air coolers?

A) To allow the release of trapped air or gases from the cooling system

C) To increase the pressure of the air within the cooler

B) To adjust the temperature of the air before it enters the engine

D) To monitor the coolant level in the air cooler

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1. Advantages of Pulse Systems

Question: What is one of the main advantages of using a pulse system in a turbocharged diesel engine?

B) It enhances the efficiency of the turbocharger by improving turbine response and reducing turbo lag

A) It reduces the overall weight of the turbocharger

D) It simplifies the engine's fuel injection system

C) It eliminates the need for a separate intercooler

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Purpose of the Diffuser in Turbochargers

Question: What is the primary purpose of the diffuser in the construction of a diesel engine turbocharger?

B) To reduce the pressure of the exhaust gases before they reach the turbine wheel

D) To filter out impurities from the intake air before it reaches the compressor

C) To slow down the high-velocity air exiting the compressor and convert kinetic energy into increased pressure

A) To increase the temperature of the compressed air before it enters the intake manifold

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Possible Causes of Poor Turbocharger Performance

Question: What are possible causes of poor turbocharger performance? (Select FOUR)

B) A malfunctioning fuel injector

F) Low engine oil level

D) A worn-out or damaged turbocharger turbine

E) A restricted exhaust system

C) An air leak in the intake system

A) A clogged air filter

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4. Turbocharger and Exhaust Gases

Question: What role do exhaust gases play in the operation of a turbocharger?

B) They power the turbine, which drives the compressor

A) They are recirculated into the intake manifold to reduce emissions

C) They cool the turbocharger to prevent overheating

D) They are vented directly to the atmosphere without any impact on the turbocharger

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2. Impact of Air Cooler on Engine Performance

Question: How does an air cooler improve the performance of a diesel engine when fitted after a turbocharger?

C) By filtering out impurities from the intake air before it enters the engine

D) By preventing the turbocharger from overheating during operation

A) By reducing fuel consumption and increasing power output

B) By slowing down the engine's RPM and reducing wear

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Components of a Resilient/Flexible Engine Mounting

Question: In a cross section through a resilient/flexible mounting for a diesel engine, what are the MAIN components typically found? (Select THREE)

E) Shock absorbers

D) Rubber or elastomeric pads

A) Mounting brackets

C) Engine support beams

B) Vibration isolators

F) Fastening bolts

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Indications of Poor Turbocharger Performance

Question: What are possible indications of poor turbocharger performance? (Select FOUR)

A) Increased turbo lag and delayed acceleration

C) Higher engine oil temperature than usual

E) Decreased engine coolant temperature

D) Unusual whining or rattling noises from the turbocharger

B) Excessive exhaust smoke or black smoke from the engine

F) Reduced power output and overall engine performance

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