Lv2 Engine Operation and Repair

Open Ended

If a 4-cylinder engine has a bore of 75mm and a stroke of 88.3mm, how would you calculate its cubic capacity?

Multiple Choice

Why is understanding engine operation and repair important for vehicle maintenance?

• It helps in diagnosing and fixing vehicle problems efficiently.

• It is only useful for car designers.

• It is not relevant for everyday drivers.

• It is mainly for racing cars.

Open Ended

What are some important safety rules you should always follow in a workshop or classroom setting?

Multiple Select

Which of the following are functions of the combustion chamber in an engine cylinder?

• Igniting compressed air, fuel, and spark

• Producing power during the four-stroke cycle

• Housing the piston

• Serving as the ignition area within the cylinder

Multiple Choice

Which stroke in a four-stroke engine involves the piston moving down and the intake valve opening?

• Compression stroke

• Intake stroke

• Power stroke

• Exhaust stroke

Open Ended

Describe the sequence of events in the four-stroke cycle of an internal combustion engine.

Fill in the Blank

The rapid expansion of gases during the ___ stroke forces the piston down powerfully.

Fill in the Blank

A correct firing order in an engine helps to minimize ___ and ensure smooth power delivery.

Open Ended

Explain the importance of firing order in engine operation and how it affects engine performance.

Multiple Choice

Which stroke in a four cylinder SI engine is responsible for igniting the air-fuel mixture?

• Suck

• Compression

• Ignition

• Exhaust

Fill in the Blank

The firing order of a four cylinder engine is ___ .

Open Ended

Explain the advantages of using an inline 4-cylinder engine configuration in modern vehicles.

Multiple Choice

Which of the following statements about valve timing is correct?

• Valve timing is less accurate at high rpms with overhead camshaft design.

• Valve timing is more accurate at high rpms with overhead camshaft design.

• Valve timing does not affect engine performance.

• Valve timing is only relevant for diesel engines.

Multiple Choice

What are two main disadvantages of increasing the number of valves per cylinder in an engine?

• Higher manufacturing costs and higher maintenance costs

• Lower engine rpm and reduced fuel efficiency

• Decreased volumetric efficiency and increased emissions

• Reduced spark plug efficiency and lower air flow

Open Ended

Describe how the camshaft operates the engine valves and the role of the crankshaft in this process.

Multiple Choice

Which component in the valve train is responsible for opening and closing the valves in an internal combustion engine?

• Camshaft

• Valve spring

• Rocker arms

• Piston

Open Ended

Explain the significance of Top Dead Centre (TDC) and Bottom Dead Centre (BDC) in relation to valve timing.

Multiple Choice

Which of the following statements about valve control and optimized valve action is correct?

• The camshaft controls valve opening and closing precisely.

• Inlet valve always opens exactly at TDC.

• Exhaust valve always closes exactly at BDC.

• Valve action is not affected by piston position.

Open Ended

What do you know about valve lag, lead & overlap?

Multiple Choice

During which stroke does the piston move down and the induction process occur in a four-stroke engine?

• Compression stroke

• Power stroke

• Induction stroke

• Exhaust stroke

Fill in the Blank

Inlet valve lag occurs during the start of the compression stroke a few degrees after ___ Dead Centre (___).

Open Ended

Explain the importance of valve overlap in engine performance and efficiency.

Multiple Choice

What is the total crankshaft revolution (in degrees) for which the inlet and exhaust valves are open, according to the diagrams?

• 180°

• 213°

• 360°

• 90°

Multiple Choice

Which of the following best describes valve overlap in an internal combustion engine?

• Both inlet and exhaust valves are closed at the same time.

• Both inlet and exhaust valves are open at the same time.

• Only the exhaust valve is open.

• Only the inlet valve is open.

Multiple Select

Which of the following statements about compression ratio is/are correct?

• A higher compression ratio generally means more power and better fuel economy.

• A lower compression ratio allows the use of lower octane fuel.

• A lower compression ratio is often used in turbocharged engines.

• A higher compression ratio requires higher octane fuel to prevent engine knocking.

Fill in the Blank

Fill in the blank: The compression ratio is the ratio of cylinder volume before and after ___.

Open Ended

What questions do you still have about vehicle engine operation and repair after today's session?

Multiple Choice

What is one important safety rule to follow if the fire alarm sounds during class?

• Exit the building via the nearest exit and meet on the grassed area by the basketball court.

• Continue working until told otherwise.

• Wait for the teacher to give instructions before moving.

• Ignore the alarm if you think it is a drill.