4.1 What is the function of the computerised diagnostic scanner used on a motor vehicle? A To scan whether the engine leaks gases from the cylinder during the induction stroke B To scan whether the engine leaks gases from the cylinder during the power stroke C To scan all systems on the vehicle and to adjust different sensors D To scan the engine of the vehicle and to adjust all engine components 4.2 Which ONE of the following pieces of equipment is used to test the crankcase gases? A Torsion tester B Gas analysing tester C Tense tester D Combustion tester 4.3 What is the volumetric efficiency of a centrifugal blower? A The ability to fill the cylinder with air above the barometric pressure B The ability to fill the cylinder with air below the barometric pressure C The ability to fill the cylinder with air above the atmospheric pressure D The ability to fill the cylinder with air when the cylinder is balanced 4.4 What could be the following cause of crankshaft vibrations? A Taper of the crankshaft journal B Crankshaft is misaligned C Crankshaft is not balanced D Crankshaft bearing is worn 4.5 Which ONE of the following is an important method used to increase the compression ratio of an engine? A Fit a thinner gasket between the cylinder block and the cylinder head - NSC Mechanical Technology Automotive - Question 4 - 2020 - Paper 1

Worked Solution & Example Answer:4.1 What is the function of the computerised diagnostic scanner used on a motor vehicle? A To scan whether the engine leaks gases from the cylinder during the induction stroke B To scan whether the engine leaks gases from the cylinder during the power stroke C To scan all systems on the vehicle and to adjust different sensors D To scan the engine of the vehicle and to adjust all engine components 4.2 Which ONE of the following pieces of equipment is used to test the crankcase gases? A Torsion tester B Gas analysing tester C Tense tester D Combustion tester 4.3 What is the volumetric efficiency of a centrifugal blower? A The ability to fill the cylinder with air above the barometric pressure B The ability to fill the cylinder with air below the barometric pressure C The ability to fill the cylinder with air above the atmospheric pressure D The ability to fill the cylinder with air when the cylinder is balanced 4.4 What could be the following cause of crankshaft vibrations? A Taper of the crankshaft journal B Crankshaft is misaligned C Crankshaft is not balanced D Crankshaft bearing is worn 4.5 Which ONE of the following is an important method used to increase the compression ratio of an engine? A Fit a thinner gasket between the cylinder block and the cylinder head - NSC Mechanical Technology Automotive - Question 4 - 2020 - Paper 1