Certificate of Qualification (C of Q) 310T Truck and Coach Technician – Engine Practice Test

These questions are part of the practice quiz. Start practicing

• What causes wet liner cavitation?
• Fiberglass fans with flexible pitch blades are designed to drive air at greatest efficiency at which speeds?
• Which of the following engine brakes offers progressive step braking using from one to all six cylinders?
• What is a disadvantage of an articulating piston assembly when compared to an aluminum alloy trunk piston?
• What is the primary purpose of an engine's harmonic balancer?
• What is the primary function of the engine in a truck and coach?
• What condition would most likely cause high silicon levels in a used engine oil analysis profile?
• What could excessive clearance at the crankshaft main bearings result in?
• What essential parameter is measured during a leak down test?
• What is the role of the engine block?
• What could happen if the timing belt fails?
• How can carbon buildup affect engine performance?
• Most current heavy duty diesel engine cylinder blocks are manufactured from which material?
• What is the main role of the thermostat in an engine cooling system?
• The location on a cam profile that is exactly opposite the toe is referred to as the?
• What factor primarily determines when to change the air filter in a diesel engine?
• What does an increase in silicon levels in an oil analysis not typically indicate?
• What is the critical flow area managed by a VG turbo using a variable nozzle?
• What should you do if you notice an engine misfire?
• Why does an engine typically achieve peak brake power at higher RPM than peak torque?
• Describe the function of the camshaft.
• What could be a consequence of not replacing a clogged air filter on time?
• When will any kind of engine brake usually operate at peak efficiency?
• The main reason for bench pressure testing a diesel engine cylinder head is to?
• What is the purpose of the timing belt in an engine?
• When an internal engine compression brake is actuated, where does gas blowdown occur?
• What describes the function of a VG turbocharger under high engine load?
• Which operating mode would be more likely to result in a compressional failure of a connecting rod?
• Which cooling media would transfer heat most efficiently?
• What is an indication of improper coolant flow?
• Which SAE multigrade oil is likely recommended for year-round use in North America?
• What are the common types of engines used in trucks and coaches?
• A camshaft gear is usually precisely positioned on the camshaft using a?
• The operating principle of an internal engine compression brake is to convert the engine into an?
• Which piston crown design is most commonly used by OEMs in today’s highway diesel engines?
• What is a potential result of a high crankcase oil level?
• When using series turbocharging in a diesel engine, how are the twin turbos arranged?
• When investigating low oil pressure, which should be done first?
• What is the primary function of the throttle body?
• What happens during an engine oil change?
• What color is used to denote a DEF fill cap?
• What could lack of maintenance on an EGR system lead to?
• How can you identify fuel contamination in engine oil?
• When a Caterpillar BrakeSaver is used, which of the following is also true?
• When comparing brake power measured at the flywheel with that at the drive wheels, what is generally true?
• Which factor is necessary to achieve peak torque in a diesel engine?
• Where does scavenging take place on a four-stroke cycle diesel engine?
• Once a cylinder head gasket fire ring has been torqued to its yield point, what should be done?
• How can underperformance in a vehicle often be initially diagnosed?
• Which of the following tools should be used to check a cylinder head for warpage?
• Which of the following best describes the intended function of a C-EGR system on a diesel engine?
• What is the correct course of action when a WIF alert is posted to the DDU?
• Which solution would provide the highest level of antifreeze protection?
• What is one reason for a misfire that could trigger the check engine light?
• What typical symptoms indicate fuel system issues?
• Which of the following is part of the leak down test process?
• Which statement best describes viscosity?
• Which method is best for locating a hole or tear in an air filter element?
• Oil that has a milky, clouded appearance is likely contaminated with?
• What is the primary function of a piston in an internal combustion engine?
• Rod and main journal bearing clearances are best measured with which tool?
• What might cause an engine to overheat?
• Which of the following is true of a CFA piston?
• When comparing an engine with high torque rise to its standard version, which aspect does it improve?
• In the event of an engine overheating, where is the coolant likely to boil first?
• An auxiliary oil pump designed to feed oil to the lubrication circuit at extreme working angles is known as a(n)?
• Which of the following should be performed first when checking an engine that produces black smoke under load?
• Which of the following actions should be performed first in response to a WIF alert?
• What is the purpose of the crankshaft in an engine?
• Ideally, where should peak cylinder pressure occur during the power stroke?
• When running an engine at idle speed, which would typically be the optimum location to peak the cylinder pressure?
• What might indicate a faulty throttle body?
• Which of the following methods is used to transfer drive from the crankshaft to the camshaft on most commercial diesel engines?
• What term describes the cylinder volume between the piston upper compression ring and its leading edge?
• What is the primary purpose of a water separator in a fuel system?
• What indicates that a diesel engine air filter needs changing?
• Describe the role of a catalytic converter.
• How is a "knocking" noise in an engine generally identified?
• How can you check the oil level and condition in an engine?
• Which portion of a typical downflow-type radiator is the warmest when the engine is at operating temperature?
• What is a common symptom of a failing water pump?
• When observing a disassembled engine, the outer crown edges of all six pistons show signs of melting and erosion. What could be the cause?
• Which of the following would best describe the color of DEF?
• Engine breathing in the two-stroke cycle is usually referred to as?
• When does a diesel engine turbocharger achieve its highest rotational speeds?
• Why should air filters be regularly inspected and replaced?
• What are throw-out bearings used for in a diesel engine?
• What does the term “engine knock” describe?
• What is the operating principle of a typical coolant pump on a highway diesel engine?
• What type of antifreeze solution is often considered the most effective for engine protection?
• Which type of diesel engine coolant is considered potentially the most harmful to humans?
• A crankshaft has a fracture failure that appears to have initiated at a throw journal oil hole. Which of the following is a more likely cause?
• What are piston rings used for?
• Which of the following best describes the function of a wastegate in a current turbo-boosted diesel engine?
• What happens if the water separator sump is not drained after a WIF alert?
• What role does engine oil play in the operation of an engine?
• What are common signs of a blown head gasket?
• What is the significance of engine timing specs?
• Which of the following is true of an APCS?
• Which of the following strategies is a requirement for starting diesel engines in subzero (below −17°C) temperatures?
• The effective braking cycle on most internal engine compression brakes fitted to hydromechanical engines is actuated by using which of the following?
• At what engine operation condition is the constant geometry turbocharger designed to produce optimum efficiency?
• What is required when cylinder block counterbores are machined?
• What is the more likely outcome of running an engine with a failed vibration damper?
• The tendency of an object in motion to want to stay in motion is known as?
• What does it mean when engine power is calculated instead of tested?
• Which component controls the drive efficiency of a thermatic, viscous drive fan hub?
• What is the purpose of an oil cooler?
• What instrument do most OEMs recommend for checking the degree of antifreeze protection in heavy duty diesel engine coolants?
• Which property of oil is directly related to its ability to flow under pressure?
• Which law explains the convertibility of all energy forms?
• What is the significance of oil viscosity in engine performance?
• A typical maximum specified inlet restriction for an air filter on a turbocharged diesel would be?
• What is a common sign of low coolant in an engine?
• Which of the following accurately describes engine displacement?
• When should a diesel engine air filter be changed?
• What does regular maintenance of the cooling system involve?
• In what area of a Mexican hat combustion chamber are the injected droplets of fuel directed?
• If a full flow oil filter is completely clogged, what is the likely outcome while the engine is running?
• Why is milky oil commonly an indicator of coolant contamination?
• Which of these is NOT a typical symptom of alternator failure?
• Which of the seven subcircuits of the engine deals with the camshaft, valvetrains, and mechanical actuation of injectors and fuel pumping apparatus?
• Engine oil service classifications are standardized by which of the following organizations?
• Which of the following types of filters has the highest filtering efficiencies?
• Describe a potential consequence of running an engine with low oil.
• What does 'engine retarding' refer to in diesel engines?
• What is the primary function of a scavenging pump in a lubrication system?
• What is the primary function of an exhaust gas recirculation (EGR) system?
• Which of the following operating conditions would be more likely to cause a valve float condition?
• How often should diesel engine air filters typically be checked?
• What safety measure should be followed when working on an engine?
• What does the term "compression ratio" refer to in an engine?
• When crankshaft thrust surfaces are reground, what is true?
• What type of oil pump is most commonly used in current highway diesel engines?
• How often should engine oil be checked for optimal performance?
• How does a diesel engine differ from a gasoline engine regarding ignition?
• What is the term for usable power at the flywheel of an engine?
• How does a fuel pump function in a vehicle’s fuel system?
• How does proper engine tuning impact fuel efficiency?
• What percentage of the potential heat energy of the fuel does the modern diesel engine convert to kinetic energy when it is operating close to optimum efficiency?
• When cavitation damage is evident on a set of wet liners, which of the following is more likely to be responsible?
• What indicators might suggest that an engine is running too rich?
• Which of the following tools is recommended for checking cylinder block line bore?
• What does the presence of white smoke emissions typically indicate?
• Where does the crank throw leverage peak within the engine cycle?
• Which tool would be required to measure the cam lift of a cylinder block-mounted camshaft in position?
• In a diesel-powered highway truck at operating temperature, which of the following is true about coolant temperatures compared to lube oil temperatures?
• What is a common inspection method for piston ring end gap?
• What type of engine brake employs the exhaust stroke of the piston as its retarding method?
• In which direction must a camshaft be rotated on a diesel engine with a crankshaft that is rotated clockwise?
• Which component is primarily responsible for reducing engine vibration?
• What could cause excessive cylinder wear in an engine?
• Which of the following engine conditions would be the likely cause of a tensile failure of a connecting rod?
• Which of the following is the recommended method of pulling dry liners from a cylinder block?
• What does coolant silicate drop-out usually cause?
• Which API classification indicates oil formulated for diesel engines meeting 2010 emissions standards?
• Why is it important to check for vacuum leaks in the intake system?
• What type of diagnosis tool is typically used for engine management systems?
• How can you verify if an engine is properly tuned?
• What is NOT typically a cause for overheating in an engine due to low coolant?
• What common tool is used to measure cylinder compression?
• What maintenance is essential for a diesel particulate filter (DPF)?
• What should be used to install piston rings onto a piston?
• What coolant temperature will produce minimum slip drive for a thermatic viscous fan hub rated at 155°F (68°C)?
• What term describes the energy associated with motion?
• Why is it essential to check the condition of spark plugs?
• Which process follows draining the water separator when a WIF alert is activated?
• When the engine is at operating temperature, how do the relative temperatures of coolant and lubricant typically compare?
• Under which of the following conditions would a piston ring seal more effectively?
• What could cause the check engine light to turn on?
• How often should engine coolant be replaced?
• If a radiator cap pressure valve fails to seal, what would be the likely outcome?
• The leak down test primarily assesses the condition of which engine components?
• Why is a turbocharger used in diesel engines?
• How do synthetic engine oils differ from conventional oils?
• Which of the following dimensions would be consistent with a typical engine timing gear backlash setting?
• What type of cam geometry is required if the objective is to load the train that rides it for most of the cycle?
• The energy of vehicle motion is ultimately converted to what energy form when an engine compression brake is used?
• Which component would you find in a diesel exhaust gas aftertreatment canister?
• What symptoms may indicate an issue with the alternator?
• Which of the following correctly identifies the source of diesel engine oil?
• To produce peak manifold boost from a VN-type turbocharger, where should the vanes be positioned?
• Which of the following engine lubricants must be used if an engine is equipped with a DPF?
• When the thermostat routes the coolant through the bypass circuit, what is primarily happening?
• What type of piston is favored by diesel engine OEMs in post-2007 products?
• How does a common rail fuel injection system enhance diesel engine performance?
• What is the main benefit of using a distilled water and EG solution?
• Which journal surface hardening method provides the highest machinability margin?
• What does a "low oil pressure" warning indicate?
• When grinding a valve face to remove pitting, the critical specification to monitor during machining would be the?
• Which of the following can be corrected by tuning the engine?
• At what position is cylinder pressure typically optimized when running an engine at rated speed and load?
• When grinding a new set of cylinder valve seats, which of the following should be performed before the machining?
• When boiling out a cylinder block, why is it critical that all the scale in the water jacket be removed?
• Explain the function of the fuel injector.
• What is a common cause of connecting rod bearing failure?
• Why is a 50/50 solution of EG and distilled water optimal for antifreeze protection?
• When a modern diesel engine is running at optimum efficiency, the percentage of rejected heat would typically be?
• Where would a Ni-Resist insert be located in an aluminum trunk piston?
• Why is it critical to monitor the coolant level in an engine?
• On a cam profile described as mostly inner base circle, the profiles between IBC and OBC are known as?
• Which of the following types of pistons use bushingless pin bosses?
• What would be the consequence of a misdirected piston oil cooling jet?
• Which component's primary job is to regulate the air entering the engine?
• What is a significant safety concern with ethylene glycol (EG) coolant?
• The cooling system hoses on an engine collapse when the unit is left parked overnight. What is the likely cause?
• The tool of choice to accurately check the inlet restriction of a dry air filter would be a?
• Which of the following cylinder block designs would be the most common in medium and heavy duty truck diesel engines?
• The reason for using a pair of oppositely wound valve springs is to?
• Why is it important to follow proper maintenance practices for diesel engine components?
• Which of the following is usually the preferred OEM method of testing an oil cooler bundle?
• Which engine brake utilizes the compression stroke of the piston for retarding?