Pressure of fuel delivery out of a positive displacement pump increases as __________

Technician A says that restriction occurs across the fuel filter when it begins to load with contaminants. Technician B says that filter contamination can be check by connecting a vacuum gauge with a T-fitting or service port between the transfer pump and primary filter. Who is correct?

Technician A says that any air in the fuel system will prevent the fuel from properly pressurizing. Technician B says that if there is air inthe fuel system, the engine will quit or not start at all. Who is correct?

Technician A says that diesel fuel systems do not require fuel return circuits. Technician B says that almost all diesel fuel systems havefuel return circuits to allow fuel to circulate through the injectors and other fuel system components to remove vapor and lubricate andcool fuel system components. Who is correct?

Technician A says that flash point is the temperature to which fuel must be heated to produce a flammable vapor. Technician B says that if the flash point of fuel is too low, it is prone to accidental ignition. Who is correct?

Technician A says that the typical temperature range at which fuels thicken and no longer flow is 20–30°F below the cloud point. Technician B says at

low temperatures, paraffin wax molecules can clump together, clouding and eventually gelling diesel fuel. Who is correct?

Technician A says that less-dense fuel has a lower specific gravity and has less energy content. Technician B says that less-dense fuel has a higher

specific gravity and less energy content. Who is correct?

Technician A says that a purpose-made fuel hydrometer is used to measure the API number of diesel fuel. Technician B says fuel's API number is

directly related to the fuels grade. Who is correct?

Technician A says that the only contaminant that will affect the quality of fuel is microorganisms. Technician B says that poor quality fuel will quickly

plug fuel filters and overwhelm the fuel-water separator. Who is correct?

High-pressure fuel systems deliver fuel to the________

Injection pressures range from _____ psi to _____ psi

Functions of High-Pressure Fuel Systems. Select all that apply.

_____ Measures and delivers correct quantity of fuel to each cylinder for current load and speed conditions

Governors regulate quantity of fuel injected into a diesel engine

The Governor receives inputs, and its output controls the

Electronic Metering Controls

Software-based governor adjusts metering

Many inputs give _____ to an electronic control module (ECM)

Rhythmic change in RPM at idle speed from the governor overcompensating for changing loads is?

Diesel engines have throttle plates in their intake

What does NOP mean?

The ______ is a fuel nozzle that sprays fuel through a single hole.

Diesel engine emission is impacted by changes to injection timing

Injection rate control is the most significant advancement of Contemporary Injection

Earlier, mechanically governed fuel systems use throttle pintle injector nozzles that generate a spray pattern that provided a gradually rising rate discharge curve.

Pilot or split-shot injection is another method of rate shaping

Atomization is the breaking of fuel into smaller droplets

Injection lag is the time delay that may occur between the start of fuel pressurization and the moment when injection actually occurs

Cold engines and low ambient air temperatures = Longer ignition times

1400 RPM = 10 Degrees before TDC Advance

1500 RPM Low Load Slowest Combustion Speed Injection is?

1500 RPM Full Load Fastest Combustion Speed Injection is?

Timing must be retarded or delayed when loads increase

Engine Load and Injection Timing Loads increase = add less fuel

Engine Load and Injection Timing

increases in cylinder pressure and temperature speed up combustion

Peak cylinder pressure should occur at approximately 10-15 degrees past TDC

_______ timed fuel injection events are critical to good engine performance

Most current engines employ idle adaption, which adjust fuel metering to compensate for engine RPM changes during each revolution

The Injectors on this Engine would use?