61-Mechanical fuel pumps are operated by

(A) Cam in the cam shaft

(B) Eccentric in the crank shaft

(C) Skew gear in the cam shaft

(D) Eccentric in the cam shaft

62-Low Cetane fuel implies that

(A) It takes linger time to ignite

(B) It takes lesser time to ignite

(C) Ignites as soon as it enters the cylinder

(D) Both (B) and (C)

63-The volume of air contained above the piston when the piston is at TDC is:

(A) Clearance volume

(B) CC

(C) Swept volume

(D) Stroke volume

64-Valve overlaps occur at:

(A) The end of exhaust valve

(B) The beginning of power stroke

(C) The beginning of compression stroke

(D) The end of power stroke

65-Thermostat valve helps the engine to:

(A) Keep the oil temperature at operating values

(B) Keep the coolant temperatures at operating values

(C) Prevents the engine from overhauling

(D) Both (B) and (C)

66-Piston rings are provided to:

(A) Completely seal the combustion gas

(B) Hold the piston concentric to cylinder walls

(C) Hold a fine oil film on cylinder walls

(D) Both (A) and (C)

67-The upper and lower ends of the combustion chamber is formed by:

(A) Piston and cylinder block

(B) Cylinder walls and piston

(C) Piston rings and cylinder head

(D) Cylinder head and piston

68-Some automobile engines have glow plugs to:

(A) Warn the driver about engine overheat

(B) Preheat the fuel for easier starting

(C) Preheat the combustion chamber

(D) Warm the passenger area

69-The main purpose of piston pin offset is to:

(A) Perfectly balance the piston during power stroke

(B) Prevent piston slip

(C) Centralize the piston

(D) Reduce piston slip

70-In an engine having swirl combustion chamber:

(A) More air fuel mixture enters

(B) Improved scavenging takes place

(C) Improved combustion takes place

(D) Burned gas has no back pressure

ANSWERS:

61-(D), 62-(A), 63-(A), 64-(A), 65-(D), 66-(D), 67-(D), 68-(B), 69-(D), 70-(C) f