Internal Combustion Engine 2013 Objective Paper

133) The purpose of heat dam used in some diesel engine cast iron pistons is to

a)concentrate all heat in the piston crown

b)increase the distance of travel for heat from the crown to the top ring groove

c)ensure that all heat in the piston crowns is conducted to the top ring

d)provide a short direct path for heat to flow from the crown to the top ring


134) Valves used in diesel engine fuel oil pressure piping are to be

a)installed to close against flow

b)solenoid released upon the failure of engine lubrication

c)either of the gate or globe valve type

d)forge constructed under the approval of the Marine Inspector


135). Cast iron pistons used in large propulsion engines are constructed with

a)no taper whatsoever

b)the skirt being tapered and smaller than the crown

c)the skirt being tapered and larger than the crown

d)the crown being tapered and smaller than the skirt


136) The diameter of a piston is usually less at the crown than at the skirt, in order to

a)facilitate the installation of piston rings

b)allow for the expansion of the piston during operation

c)prevent crankcase vapors from entering the combustion chamber

d)reduce wearing of the upper cylinder liner


137). Which of the following manufacturing methods is recommended for diesel engine fuel injection line piping?

a)Cold rolled

b)Electric resistance welded

c)Seamless drawn

d)Straight seam


138) Exhaust pipes of multiple engine installations are not to be interconnected, but are to be run separately to the atmosphere

a)unless arranged to prevent the return of gases to an idle engine

b)to a point not lower than the highest load line

c)at a location segregated from other ventilation systems

d)and shall be protected by a rain guard or similar device


139) Which of the bearing types listed is most commonly used in smaller vessel main propulsion reduction gears as thrust bearings?

a)ball bearings

b)poured bearings

c)sleeved bearings

d)tapered roller bearings


140) The main reason for using bimetallic piston rings is to

a)increase engine thermal efficiency

b)reduce specific fuel consumption

c)reduce the probability of ring fracture

d)allow for ring expansion


Prepare for MMD Class 4 Objective