Millwright level 4 INTERNAL COMBUSTION ENGINES Exam Questions With Verified Answers

Millwright level 4 INTERNAL COMBUSTION ENGINES Exam Questions With Verified Answers Before performing maintenance on a recently run engine, you must: A) Drain all oil from the crankcase B) Check and record the hour meter C) Disconnect all electrical, close, lock, tag and purge all gas sources D) Contact the manufacturer - answerC) Disconnect all electrical, close, lock, tag and purge all gas sources The thermal efficiency of an engine is best described as: A) Draw in a full charge of air to produce power B) efficiently run in a smooth and effective manner C) change the energy in the fuel to usable heat energy and power D) burn the fuel wit the least amount of power lost to friction - answerD) burn the fuel wit the least amount of power lost to friction The Amount of air an engine is able to take into the cylinder compared with the volume of the cylinder is called: A)scavenging efficiency B) cycle efficiency C) Thermal efficiency D) Volumetric efficiency - answerD) volumetric efficiency The description of compression ratio is best described as: A) the cylinder volume divided by the combustion chamber volume B) the cylinder volume plus the combustion chamber volume, divided by the combustion chamber volume C) the cylinder volume plus the displacement volume, divided by the combustion chamber volume D) the total displacement of the engine divided by the combustion chamber volume - answerB) the cylinder volume plus the combustion chamber volume, divided by the combustion chamber volume On a 2-stroke engine with 6 cylinders and a firing order of 1-5-3-6-2-4, the running mates would be: A) 1-6 5-4 3-4 B) 1-3 2-4 5-6 C) 1-4 5-2 3-6 D) none of the above - answerD) none of the above When comparing a diesel engine to a gas engine, the: A) compression pressures may be twice as high or greater in a diesel engine B) compression ratios are approximately twice as high or greater in a diesel engine C) Diesel engine is heavier D) All of the above - answerD) All of the above When air is compressed, what are the noticeable effects? A) The volume increases but the temperature remains constant B) the temperature increases, as the volume decreases C) The pressure increases w/o a temperature increase D) Volume has no effect on the temperature - answerB) the temperature increases, as the volume decreases The SI metric system measures pressure in: A) cubic centimeters B) pascals C) newtons D) watts - answerB) pascals When you are determining engine rotation using the SAE standard, you view the engine from: A)the fan or the front of the vehicle B) the main power end of the engine C) the side with the flywheel on the left D) either the flywheel or the front balancer - answerB) the main power end of the engine Which type of head design has the valves in the block? A) an I head engine B) a wedge-type engine C) an L head engine D) a multi-valve-type engine - answerC) an L head engine Indicated horsepower is the power at the flywheel of the engine. True or False? - answerFalse. Indicated HP is the engine's theoretical HP. A 2-Stroke engine completes on cycle in 720 degrees of rotation. True or False - answerFalse. This is done in 360 degrees. 4 strokes complete their cycle in 720 degrees. Potential energy is the energy resulting from the motion of an object. true or false - answerFalse. Kinetic energy is the result of a moving object. An undersquare engine is an engine with a larger stroke than bore. True or False - answerTrue Blowby is leakage past the rings. T OR F - answerTrue Running mates are pistons that reach TDC at the same time. T OR F - answerTrue The basic requirement for combustion is air, spark, and compression.