Exam 12: Engine Breathing

After running a diesel engine under heavy load, how long should the engine be idled before shutdown?

When a turbocharger is set up to impart drive torque to the crankshaft, which of the following terms describes the system?

What is used as the cooling medium in heat exchangers known as aftercoolers and intercoolers?

While pressure testing an isolated Cummins charge air cooler (CAC), the pressure drops from 30 psi to 25 psi in 15 seconds. Technician A says that the CAC is leaking. Technician B says that the pressure drop-off is within specification and the CAC can be returned to service. Who is correct?

When a rain cap is used on a vertical exhaust stack, in which direction should the opening flap be pointed?

Which of the following does most to define how fast a turbocharger rotates?

Which of the following operating conditions is more likely to cause a diesel engine, catalytic converter to plug?

Technician A says that a VG turbocharger functions like a small turbo when engine loads are light. Technician B says that a VG turbocharger functions like a large turbo when engine output is high. Who is correct?

What is used in conjunction with an EGR system on most commercial diesel engines?

Where would you most likely find a thermocouple pyrometer on a current highway diesel engine?

What component rotates in the compressor housing of a turbocharger?

Which of the following is an example of a tuned diesel engine exhaust manifold?

Which of the following best describes the role of an exhaust gas recirculation (EGR) system on a current diesel engine?

Which of the following steps must be performed after installing a reconditioned turbocharger?

Which of the following components would be associated with a variable geometry turbocharger?

Which sound dampening principle is based on sound waves being reflected back toward their source?

Which of the following statements best describes how EGR functions to reduce NOx emissions?