Week #5 - Basic Fuel Systems Flashcards
True or False: DEF is available at most diesel refueling stations.
True
The theory that explains the atomic differences in the three states of matter is known as what?
Kinetic molecular theory
Calculate the stoichiometric requirement of a fuel composed of 84% carbon, 15% hydrogen, and 1% sulfur when combusted in ambient air.
14.96: 1
An injector spring in a hydraulic injector nozzle that is fatigued would likely produce which of the following conditions?
a. Nozzle chatter
b. Lower NOP and advanced injection timing
c. Higher NOP
d. Higher NOP retarded injection timing
b. Lower NOP and advanced injection timing
In which engine position does the crank throw provide the least amount of leverage?
a. 15 degrees ATDC
b. 90 degrees ATDC
c. BDC
d. TDC
d. TDC
True or False: Diesel fuel tends to be more volatile than gasoline.
False
Which of the following solutions would provide the highest level of antifreeze protection?
a. A 100% solution of PG
b. A 100% solution of EG
c. A 50/50 solution of EG and distilled water
d. Pure distilled water
c. A 50/50 solution of EG and distilled water
True or False: EG is always colored green.
False
Which of the following specific gravity values would correspond to that of a typical #2D diesel fuel?
a. 0.840
b. 0.710
c. 1.170
d. 0.970
b. 0.840
Atomized droplets are in a gaseous state.
False
When attempting to cold-start an electronically controlled diesel engine in subzero (lower than -70 degrees C) conditions, which of the following would provide the most help?
a. Smaller than normal fuel droplet sizing
b. Larger than normal fuel droplet sizing
c,. Pushing the accelerator to the floor
d. Substantial advance to injection timing
a. Smaller than normal fuel droplet sizing
True or False: Some water-separator units use a centrifuge to separate water from fuel.
True
True or False: The end products of both an explosion and a combustion reaction are similar.
True
True or False: The laws of thermodynamics dictate that a catalytic reaction must involve a change in the state of the catalyst.
False
True or False: The stoichiometric requirement of a diesel fuel ranges between 14.5:1 and 15.1:1.
True
True or False: All #1D and #2D fuels must be sold with a CN number of exactly 40.
False
True or False: At refueling on the completion of a journey, fuel is steaming in the tanks. This condition is a result of normal operation in some fuel systems.
True
True or False: Injector nozzles used on pre-2007 EUIs and HEUIs use the same operating principles as those on any hydraulic pump-line-nozzle system.
True
The most abundant element found in the known universe is what?
Hydrogen
True or False: The degree of atomization is controlled by managing injection pressure.
True
True or False: Most commercial truck diesel engines use a vane-type transfer pump located in the fuel tank to pump fuel to the transfer pump.
False
True or False: Denser fractions of crude petroleums tend to command higher prices than lighter fractions.
False
True or False: An isochronous governor is normally used to manage a genset.
True
How many protons would a balanced atom of oxygen contain?
8
The atomic number of an element indicates the number of _____ in an atom of the element.
Protons
The smallest particle of a compound that can exist in the free state and retain the chemical identity of the compound is know as a(n) _____.
Molecule
Oxygen has a valence of ____.
2
If a four-stroke cycle engine is run at 1,000 rpm, approximately how many power strokes per second will occur in any one of its cylinders?
17
Nozzle differential ratio is a ratio of:
a. The high-pressure pipe sectional area and the orifii flow area
b. Nozzle seat sectional area and total nozzle sectional area
c. The mechanical spring force and hydraulic pressure
d. The nozzle pressure chamber sectional area and the high-pressure pipe sectional area
b. Nozzle seat sectional area and total nozzle sectional area
True or False: In a current truck dual fuel tanks, fuel pickup tubes are located in each tank.
True
True or False: Nozzle chatter while bench-testing an injector is an indication of a fatigued injector spring.
False
What color is used to denote a DEF fill cap?
Blue
True or False: Diesel fuel can combine with air to form potentially explosive mixtures.
True
As the octane rating value of a gasoline increases, what can be said of its burn rate?
a. It increases
b. It is not affected
c. It decreases
c. It decreases
Besides fuel storage, the fuel tank may play an important role in a high-flow fuel system as a(n):
a. Aerodynamic aid
b. Heat exchanger
c. Fuel heating device
d. Ballast equalizer
b. Heat exchanger
True or False: Most truck engine OEMs recommend adding fuel conditioners to diesel fuel tanks to improve the winter drivability of diesel engines.
False
True or False: Refiners and fuel suppliers seasonally adjust the ignition quality of fuels.
True
The term used to describe a combustion reaction in which the exact proportions of fuel and air are present is ______.
Stoichiometric
True or False: Most electronically managed diesel engines are run at precise stoichiiometric ratios of air and fuel after the engine is at operating temperature.
False
On the typical truck diesel fuel subsystem, which of the following is usually subject to the lowest pressure in the circuit?
a. Primary filter
b. Fuel heater
c. Charging gallery
d. Secondary filter
a. Primary filter
True or False: When servicing fuel filters on a fuel subsystem with a primary and a secondary filter, a transfer-pump-located, hand primer pump can be used to prime both filters.
False
True or False: When diesel fuel is combusted, one of the products of combustion is water.
True
True or False: EHIs using the most common type of piezoelectric actuators should test at resistance values of 0.6 ohms or less.
True
Charging pressure rise is usually directly related to which of the following?
a. Increased rpm
b. Throttle position
c. Engine load
d. Peak power
a. Increased rpm
Which of the following is the correct course of action when a WIF alert is posted to the DDU?
a. Replace the fuel filters
b. Drain the water separator pump
c. Replace the water separator
d. All of the above
b. Drain the water separator pump
True or False: Carbon can be classified as a reactive element.
True
Calculate the stoichiometric requirement of a fuel composed of 84% carbon, 15% hydrogen, and 1% sulfur when combusted in pure oxygen.
3.34: 1
The main reason for filling vehicle fuel tanks before overnight parking is:
a. To minimize fuel evaporation
b. Drivers may forge the next morning
c. To hope cool down onboard fuel
d. To minimize moisture condensation within the tank
d. To minimize moisture condensation within the tank
As the CN value of a diesel fuel increases, what happens to its ignition temperature?
a. It increases
b. It is not affected
c. It decreases
c. It decreases
Which type of injection nozzle would be found on most DI truck diesel engines before 2007?
Multi-orifii
True or False: An explosion is an oxidation reaction that occurs in much less time than what would be described as combustion in an engine cylinder.
True
What type of pumping principle is used by a typical hand primer pump?
Single-acting plunger
True or False: The opening and closing of an EHI are controlled by the ECM.
True
If the fuel tank vent valve on a diesel-powered vehicle is plugged, which of the following would be the likely outcome when running the engine?
a. The engine would run away due to excess fuel
b. The engine would shut down due to fuel starvation
c. The tank would explode
d. The tank would implode
b. The engine would shut down due to fuel starvation