02_1 Engine General

The correct working cycle of a four stroke engine is:-

• Exhaust, power, induction, compression.

• Induction, compression, power, exhaust.

• Induction, power, compression, exhaust.

• Exhaust, induction, power, compression.

Carbon monoxide gas, which is highly toxic, may enter the aeroplane cabin in flight because of an exhaust system defect. Carbon Monoxide:

• May be identified by its strong smell.

• May be identified by its grey colour.

• Is odourless and colourless.

• Has a very distinctive taste.

The power output of an internal combustion engine can be increased by:

• Decreasing the area of the cylinder.

• Decreasing the length of the stroke.

• Increasing the engine R.P.M.

• Increasing the size of the fuel tank.

The compression ratio of a piston engine is the ratio of the:

• Total cylinder volume to the volume when the piston is at bottom dead centre (BDC).

• Total cylinder volume to swept volume.

• Cylinder volume when the piston is at BDC to the cylinder volume when the piston is at TDC.

• Swept volume to clearance volume.

The number of revolutions of the crankshaft required to complete a full cycle in a four stroke engine is:

• 6.

• 4.

• 2.

• 8.

To achieve the correct valve timing in a piston engine, the valves are opened by a camshaft running at:

• Twice crankshaft speed.

• Engine speed.

• Twice engine speed.

• Half crankshaft speed.

During one complete Otto Cycle, the piston:

• Rotates around the gudgeon pin twice.

• Moves towards the cylinder head twice.

• Receives two power strokes.

• Moves towards the cylinder head four times.

The crankshaft in a piston engine:

• Converts reciprocating movement into rotary motion.

• Controls the clearance of the valves.

• Converts rotary motion into reciprocating movement.

• Rotates at half the camshaft speed.

Engine compression ratio is the ratio of the:

• Total volume to the clearance volume.

• Clearance volume to the swept volume.

• Swept volume to the total volume.

• Swept volume to the clearance volume.

The temperature of the gases within the cylinder of a four stroke engine during the power stroke will:

• Decrease.

• Increase.

• Follow Charles's Law.

• Remain constant.