Diesel Engine Performance 12,14,15, 16, 17, 21, 22, 23, 29, 30 & 31 Quizzes

Electronically controlled fuel systems can vary injection timing to _______ of crank-angle degree. Question options: 0.1 0.2 0.3 0.5

0.1

Which is the correct firing order for a standard in-line six diesel engine? Question options: 1-5-3-6-2-4 1-2-3-4-5-6 1-6-5-2-3-4 1-3-2-5-6-4

1-5-3-6-2-4

Kerosene is very similar to which grade of diesel fuel? Question options: 3-D 2-D 1-D 4-D

1-D

How many separate injection events is a modern common rail injector capable of in one combustion event? Question options: 10 11 12 13

10

A common-rail fuel injector is capable of cycling ___________ per minute. Question options: 10,000 8,000 6,000 4,000

10,000

What is the approximate flash point for most diesel fuels? Question options: 85-95º F 100-125º F 95-105º F 110-130º F

100-125º F

To which temperature can return fuel reach during engine operation? Question options: 180º F 160º F 140º F 150º F

140º F

How many ppm of sulfur is contained in ULSD? Question options: 19 13 15 21

15

A modern diesel injector may have as many as __________ spray holes. Question options: 10 11 13 15

15 (wrong) 10 (wrong)

What rpm must an isochronous governed generator maintain to prove 60 Hz AC frequency? Question options: 1200 1500 1800 2150

1800

Approximately when did electronic governors come into use? Question options: 1970's 1980's 1990's 2000's

1990's

Which diesel fuel grade naturally produces Asphaltenes? Question options: 1-D 2-D 4-D B100

2-D

__________ of total diesel fuel is consumed by trucks, buses, and equipment. Question options: 23% 20% 26% 22%

23%

Verifying the delivery volume of a mechanical fuel pump will require the technician to crank the engine for ___________ seconds. Question options: 60 30 120 45

30

What is the NOP range for most multi-orifice nozzles? Question options: 3300-5500 psi 1200-2000 psi 2200-2800 psi 2600-3300 psi

3300-5500 psi

Which diesel fuel grade is primarily used for home heating? Question options: 2-D 3-D 4-D 1-D

4-D

Which diesel fuel type is NOT permitted to be used by on-highway vehicles? Question options: 4-D 1-D 2-D B-5

4-D

2-D diesel will need to meet the minimum requirement of CN __________. Question options: 30 40 35 45

40

To which pressure are modern fuel injection systems capable of today? Question options: 70,000 psi 65,000 psi 40,000 psi 12,000 psi

40,000 psi

Modern common rail injection systems can exceed fuel delivery pressure above ____________. Question options: 42,500 psi 40,000 psi 38,000 psi 35,000 psi

42,500 psi

Mechanical diaphragm fuel pumps will generally supply no more than __________ fuel pressure to the fuel system. Question options: 4 psi 5 psi 6 psi 7 psi

7 psi

Where is the piston located when peak cylinder pressure occurs during injection? Question options: 1-5 degrees ATDC 1-10 degrees BTDC 10-15 degrees ATDC 8-12 degrees BTDC

8-12 degrees BTDC (wrong) 1-5 degrees ATDC (wrong)

A fuel labelled B-20, will have what percentage of petroleum fuel incorporated within it? Question options: 50% 80% 60% 70%

80%

Which of the following configurations is best used by a line-haul engine? Question options: A high torque rise engine that splits the top-range gears A low torque rise engine that splits the top-range gears A high torque rise engine that splits the low-range gears A low torque rise engine that splits the low-range gears

A high torque rise engine that splits the top-range gears

Which regulatory body developed standards for measuring fuel density? Question options: CARB ASTM API SAE

API

What can be used to prevent diesel fuel from freezing? Question options: Glycol Gasoline Alcohol Kerosene

Alcohol (wrong) Kerosene (wrong)

Which injector characteristic must match the shape of the pistons combustion bowl? Question options: Number of spray holes Angle of spray holes Length of spray holes Spray hole diameter

Angle of spray holes

What state is the fuel when injected into the combustion chamber? Question options: Solid Vapor Liquid Atomized

Atomized

Where does pilot injection occur in relation to piston position? Question options: TDC BDC BTDC ATDC

BTDC

What color of smoke is emitted from the exhaust when inadequate air to fuel ratio exists? Question options: White smoke White vapor Grey smoke Black smoke

Black smoke

Technician A says that a diesel engine needs a programmable electronic governor to improve fuel economy in a commercial vehicle. Technician B says that a diesel engine needs a governor to regulate fuel delivery because diesels are very sensitive to slight changes in the amount of fuel injected and can overspeed. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Both Technician A and Technician B

Which component within the high-pressure fuel system acts upon plungers to increase fuel pressure? Question options: Rocker Camshaft Push-rod Crankshaft

Camshaft

The majority of fuel water separators work by a process called? Question options: Coalescing Absorption Vaporization Dissolving

Coalescing

Which gasket type is commonly used to seal the nozzle body to its seat? Question options: Cork Steel Plastic Copper

Copper

Where is the injector body attached? Question options: Intake manifold Cylinder head Intake pipe Exhaust manifold

Cylinder head

What is the purpose of a fuel sight glass? Question options: Measure pressure Measure fuel flow Measure restriction Detect air

Detect air

Which engine manufacturer locates a fuel cooler behind the fuel filter module? Question options: Detroit Diesel International Volvo Cummins

Detroit Diesel

Which electrical signal type is supplied to injectors within a full authority governed fuel system? Question options: Pulse width modulation Alternating current Direct current Hall effect

Direct current (wrong) Alternating current (wrong)

Which component drives a mechanical diaphragm pump to provide fuel system pressure? Question options: Eccentric lobe Intake lobe Exhaust lobe Injector lobe

Eccentric lobe

Which component within a partial authority governor varies fuel timing? Question options: Flyweights Electric solenoid Governor spring Throttle pedal

Electric solenoid

Present electronic controlled fuel systems can vary maximum and minimum injection pressures independent of ___________. Question options: Engine speed Engine torque Road speed Engine load

Engine speed

Older injector nozzles may only have had 4 or __________ spray holes. Question options: Eight Seven Six Five

Five

When injected, diesel fuel will burn ________. Question options: All at once From inside out From outside in Not at all

From outside in

Which is the largest cost associated with operating a heavy-duty commercial vehicle? Question options: Repairs Fuel Maintenance Tires

Fuel

Which fuel system component is the most serviced? Question options: Fuel lines Fuel tank Fuel filter Fuel pump

Fuel filter

Where would a technician most commonly find a diesel fuel heating devise? Question options: Fuel lines Fuel tank Fuel filter housing Fuel pump

Fuel pump (wrong) Fuel lines (wrong)

Which material should NOT be used to manufacture diesel fuel tanks? Question options: Plastic Aluminum Galvanized metal Steel alloy

Galvanized metal

Choose the incorrect condition related to a misaligned injector installation. Question options: Good combustion Fuel leak Poor air fuel mixture Incorrect spray pattern position

Good combustion

Which fluid type is used within the hydraulic governor? Question options: Hydraulic oil Gear oil Engine oil Transmission oil

Hydraulic oil (wrong) Transmission oil (wrong)

Which emission is reduced when a shorter ignition delay period occurs? Question options: Carbon monoxide Oxides of nitrogen Carbon dioxide Hydrocarbons

Hydrocarbons (wrong) Carbon monoxide (wrong)

Which factor will NOT affect combustion within a cylinder? Question options: Injector spray pattern Length of piston Piston bowl depth Piston bowl width

Length of piston

An automotive governor type is also referred as a ______________ governor. Question options: Limiting speed All-speed Pedal angle Variable speed

Limiting speed

Which engine operating condition would a hunting condition occur? Question options: High idle Low idle Rated rpm Over speed

Low idle

Which vehicle type registered in the US consumes the most diesel fuel? Question options: Buses MD trucks Refuse truck HD trucks

MD trucks (wrong) HD trucks (wrong)

Technician A says that a closed hydraulic nozzle allows combustion gases to mix with fuel inside the nozzle. Technician B says that a closed nozzle does not have a fuel return line back to the fuel tank. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Neither Technician A nor Technician B

Technician A says that any type of governor will work well when pulling heavy loads in off-road conditions without surging and causing driveline damage. Technician B says that an automotive governor is best suited to those operating conditions. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Neither Technician A nor Technician B

Technician A says that multiple injection events from an injector to reduce emissions causes an engine to produce less torque. Technician B says that multiple injection events during a combustion cycle are used to reduce heat loads in a cylinder. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Neither Technician A nor Technician B

Technician A says that a float sensor in a filter housing can be used to measure the level of water and determine when the filter should be drained. Technician B says that a probe in the bottom of a fuel filter, which measures the difference between the conductivity of water and fuel, is used to switch on the water-in-fuel warning lamp. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Neither Technician A nor Technician B (wrong)

What is the visual standard utilized by law enforcement agencies when viewing exhaust emissions? Question options: No more than 5 seconds of visible emissions in one minute of operation No more than 10 seconds of visible emissions in one minute of operation No more than 15 seconds of visible emissions in one minute of operation No more than 30 seconds of visible emissions in on minute of operation

No more than 15 seconds of visible emissions in one minute of operation

Nozzle chatter is an indication of? Question options: Forward leakage Rearward leakage Normal operation Leaking sealing surface

Normal operation

What does fuel pressure act on to lift the nozzle of its seat? Question options: Spring Spring shim Nozzle body Nozzle annulus

Nozzle annulus

Twist drilling, EDM, and laser machining are all manufacturing processes used to produce which injector component? Question options: Nozzle orifice Annular profile Nozzle body Needle valve

Nozzle orifice

Which component sprays fuel into the combustion chamber? Question options: Plunger Plunger body Nozzle valve Needle valve

Nozzle valve

Which type of operation from the list below is best suited to an engine calibrated to high torque rise operation? Question options: Off-road equipment On-highway equipment City transit bus Power generation

On-highway equipment

How often should contaminants within a fuel tank be drained off? Question options: Every two years Once a year Four times a year Never

Once a year

Which emission does biodiesel emit more of when compared to petroleum based diesel? Question options: Oxides of nitrogen Hydrocarbons Particulate matter Carbon monoxide

Oxides of nitrogen

Which emission is minimized during acceleration by air-fuel ratio control? Question options: NOx CO CO2 PM

PM

Which type of engine emissions is controlled by the air-fuel ratio device? Question options: Oxides of nitrogen (NOx) Carbon monoxide (CO) Particulate matter (PM) Hydrocarbons (HCs)

Particulate matter (PM)

The first Biodiesel fuel was manufactured from ___________ oil. Question options: Corn Peanut Coconut Soybean

Peanut

The injector must be matched to the ____________ to ensure proper proper combustion. Question options: Crevice area Pre-chamber Piston crown Piston bowl

Piston bowl

Which condition will promote scuffing of nozzle valves? Question options: Poor fuel lubricity High fuel pressure Injection pressure Combustion heat

Poor fuel lubricity

Which injection event is used to dose a DPF or LNT? Question options: Pre-injection Post-injection Square injection Ramped injection

Post-injection

What should NOT be done when replacing a fuel filter? Question options: Pre-filling the filter Use hand priming pump Use electric priming pump Bleed air with bleed screw

Pre-filling the filter

What is the purpose of the primary filter within a fuel system? Question options: Protect the injectors from premature wear Protect the fuel tank from premature wear Protect the fuel pump from premature wear Protect return check valve from premature wear

Protect the fuel pump from premature wear

Which name is best associated with the fuel delivery component that has a deformable end for fuel delivery sealing? Question options: Jump tube Fuel tube Fuel line Quill tube

Quill tube

What color is associated with dyed diesel fuel? Question options: Green Yellow Blue Red

Red

Where is the water in the fuel sensor located? Question options: Water-fuel separator Secondary filter Fuel tank Fuel pump

Secondary filter (wrong) Fuel Tank (wrong)

What holds the nozzle valve in the closed position? Question options: Fuel pressure Spring pressure Nozzle cap Nozzle body

Spring pressure

When is diesel fuel injected in a internal combustion engine? Question options: End of intake stroke Start of compression stroke End of the compression stroke Start of intake stroke

Start of compression stroke

After assembling an engine and discovering that one of the vibration-insulating, high-pressure fuel line clamps was missing, two technicians discussed potential consequences if the clamp remained missing from the injection line. Technician A says that the line will crack due to vibration caused by pressure pulses. Technician B says that a single missing clamp on thick-walled steel lines will have no effect on the line. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Technician A

Technician A says that 2-D fuel provides the most power and best fuel economy for an on-highway diesel engine. Technician B says that 1-D is the best fuel for producing power and good fuel economy. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Technician A

Technician A says that a fuel heater located in a filter housing is the best way to prevent wax and ice crystals from restricting fuel flow. Technician B says that ethanol can be used to dissolve wax and prevent water from crystalizing in fuel filters. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Technician A

Technician A says that diesel fuel's low volatility is why so many diesel fuel pump islands appear to have a lot of spilled fuel. Technician B says that fuel spills at diesel pump islands are more common than those at gasoline pumps because truck drivers are careless when refueling. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician

Technician A

Technician A says that injection lag takes place when the time between the actual beginning of injection lags behind the time when pressurization of the injector takes place. Technician B says that injection lag is caused by poor-qualityfuel with a low cetane number. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Technician A

Technician A says that it is important to push the accelerator pedal to the floor once and then release it when starting a mechanically governed diesel engine. Technician B says that the injection pump will automatically go to half throttle when cranking and nothing needs to be done. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Technician A

Technician A says that DI combustion chambers use pintle spray nozzles. Technician B says that only multi-orifice nozzles are used in DI engines. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician

Technician B

Technician A says that adding a little gasoline to diesel fuel will help a diesel engine start faster in cold weather, reduce combustion noise, and improve power output. Technician B says that adding gasoline to diesel fuel will make starting worse, increase combustion noise, and accelerate fuel system wear. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Technician B

While checking power contributions from each cylinder for a late-model, electronically controlled engine, Technician A says that the purpose of adaptive cylinder balance is to reduce combustion noise so that diesels run more quietly. Technician B says that adaptive balance reduces emissions and helps an engine run more smoothly. Who is correct? Question options: Technician A Technician B Both Technician A and Technician B Neither Technician A nor Technician B

Technician B

Microglass filters are capable of filtering contaminants down to _______ microns. Question options: One Two Four Five

Two

Which governor type is more commonly used with off-road equipment, stationary equipment, and marine applications? Question options: Automotive and variable Automotive Variable Isochronous

Variable

Which condition does NOT affect injection lag? Question options: Vehicle road speed Fuel volume Engine speed Fuel pressure

Vehicle road speed

Which operating condition is NOT controlled by a mechanical fuel system governor? Question options: Control torque rise Shut down the engine Engine speed control Vehicle road speed

Vehicle road speed

Which contaminate is the worst for diesel fuel? Question options: Dirt Water Alcohol Oil

Water

Which is the most common contaminant found in diesel fuel? Question options: Tar Oil Dirt Water

Water

Which component within the fuel system is directly after the fuel tank? Question options: Injectors Water separator Fuel pump ECU

Water separator

If a mechanically governed diesel engine can NOT reach the engine high idle as posted on the emission tag, what could cause this issue? Question options: Aneroid failure Worn delivery valve Worn segment gear Weak governor spring

Weak governor spring

What color is the lamp that illuminates when an engine fault is detected? Question options: Yellow Red Green Blue

Yellow

How is torque controlled within an on-highway Class 8 truck? Question options: Tire size Fuel quantity injected Transmission ratios Drive axle ratios

Transmission ratios (wrong) Drive axle ratios (wrong)

Which electronic governor input is controlled by the equipment operator? Question options: Throttle pedal Coolant temperature Fuel temperature Boost pressure

Throttle pedal

Nozzle dribble, misfiring, and excessive combustion noise are all symptoms of which type of malfunction? Question options: Plugged orifices Tip leakage Nozzle stuck open Excessive return fuel

Tip leakage