Mechanical Fuel Injections

A governor that has highly controlled speed droop is known as a(n) ______________ governor.

limiting speed

variable speed

isochronous

hydraulic

Correct! Wrong!

On an engine equipped with a mechanical diesel fuel system, when an operator moves the throttle through the speed ranges, he is altering the governor''s.

flyweight position

spring tension

torque spring

buffer screw

Correct! Wrong!

On a fuel injection pump utilizing the port and helix system, what position the control edge of the helix for the fuel delivery volume?

rack

sleeve

plunger

delivery valve

Correct! Wrong!

On an in-line fuel injection pump utilizing the port and helix system, what tries to maintain system line pressure for a rapid rise and fall of injection pressures?

the fuel rack assembly

sleeve metering valve

supply pump return restriction

delivery valve

Correct! Wrong!

Technician A says that a limiting speed governor attempts to keep the engine RPM at nearly constant even rate even though the load on the engine may change. Technician B says that the limitiing speed governor will control minimum engine RPM. Who is correct?

Technican A

Technican B

Both A and B

Neither A nor B

Correct! Wrong!

What controls the maximum pressure in a high pressure injector fuel line?

rack and linkages

plunger and barrel

needle, seat and orifices assm

delivery valve and closing spring

Correct! Wrong!

When a technician adjusts all the plungers so that they repeatedly produce the exact quantity of fuel, he is said to be ______________ the fuel pump.

calibrating

timing

phasing

metering

Correct! Wrong!

On a port and helix fuel pump, when the rack rotates the plunger so that the vertical groove is aligned with the fill port, the pump is said to be in the:

full fuel position

peak torque position

no fuel position

idle position

Correct! Wrong!

On a port and helix fuel pump system, when the rack rotates the plunger so that the narrowest part of the helix is aligned with the fill/spill ports, the pump is said to be in the:

full fuel position

peak torque position

no fuel position

idle position

Correct! Wrong!

Injection nozzles that open with the needle valve moving away from the combustion chamber are said to be:

inward opening

outward opening

chattering

coking

Correct! Wrong!

When working with injection nozzles, you should:

keep hands out of the path of the high pressure spray

wet hand with fuel before handling precision parts

keep parts and work ares extremely clean

all of the above

Correct! Wrong!

When bench testing a set of high pressure injection nozzles. Technician A says that when checking injection nozzles you should check the cracking pressures and forward leakage. Technician B says that you should check the spray pattern and back leakage. Who is correct?

Technician A

Technician B

Both A and B

Neither A nor B

Correct! Wrong!

A high pressure fuel injection pump that uses a rack to move a fuel volume control device up and down on the outside of the injection plunger and barrel is known as a _____________ type fuel pump.

sleeve metering

port and helix

pressure timed

distributor

Correct! Wrong!

If the device mentioned in the previous question were to be moved all the way up, the fuel pump would be in the ____________ position.

full fuel

idle

partial fuel

no fuel

Correct! Wrong!

A mechanical governor operates on the principle of:

spring tension and flyweight speed in opposition

intake manifold pressure and spring tension reacting upon a diaphragm

intake manifold pressure and flyweight speed reacting upon a diaphragm

turbo speed and spring tension on the torque shaft

Correct! Wrong!

When spill timing a fuel injection pump using the port closing method you would be dealing with a pump having helices with:

variable beginnings and variable endings

variable beginnings and constant endings

constant beginnings and constant endings

constant beginnings and variable endings

Correct! Wrong!

When mounting a fuel injection pump to an engine and adjusting the fuel pump drive so that pins will enter respective holes in the flywheel and fuel pump, you are said to be _______________ the fuel pump to the engine.

phasing

metering

calibrating

timing

Correct! Wrong!

On a diesel injected engine, if a delivery valve does not seat properly, the engine would:

show no noticeable change

miss

stall

go to maximum governed RPM

Correct! Wrong!

Technician A says that a fuel injection pump with port and helix system uses a mechanical actuated injector. Technician B says that a distributor type fuel system uses a hydraulically actuated injector. Who is correct?

Technician A

Technician B

Both A and B

Neither A nor B

Correct! Wrong!

What will occur if the cracking pressure in a high pressure nozzle is too low?

early injection

late injection

uncontrolled burn

all of the above

Correct! Wrong!

The most common injection nozzle used with direct injection is the:

multi-hole nozzle

pintle nozzle

pintaux nozzle

delay nozzle

Correct! Wrong!

The amount of RPM fluctuation from maximum RPM no load to maximum RPM full load is known as:

rated speed

peak torque

droop

hunting

Correct! Wrong!

A fuel pressure gauge test on an engine may indicate:

transfer pump pressure.

fuel filter condition

the recommended pressure at an idle and run positions

all of the above

Correct! Wrong!

On a diesel fuel system, when the governor flyweights extend, they change spring tension to move the rack to a ____________ fuel position.

increased

lesser

minimum

full

Correct! Wrong!

On a fuel injection pump system, what is the purpose of the restricted fitting in the return fuel line at the outlet of the fuel pump?

acts as a relief valve for the transfer pump

maintains transfer pump pressure

prevents injectors from receiving fuel pressure

keeps the fuel lines from draining back to the fuel tank

Correct! Wrong!

Which fuel injector type is used by Detroit 2 cycle diesels and Cummins PT injection systems and others?

unit injectors

sleeve metering

distributor type

Correct! Wrong!

Injector timing is done on a Detroit Diesel unit injectors by:

timing the pump to the engine using locator timing pins

changing shims under the cam follower housings mounting plates

lengthening or shortening the injector plunger movement

rotating the injection pump at its mounting flange

Correct! Wrong!

What is the purpose of a buffer spring in an engine governor?

adjustment to limit high engine RPM

adjustment to limit engine hunting

adjustment to limit movement of the flyweights

returns the AFC diaphragm to rest position

Correct! Wrong!

What will be the effect if injector plungers are set higher than specifications in a Detroit Diesel 2 cycle engine?

advance injection

over fuelling

retarded injection

under powered

Correct! Wrong!

Technician A says that a Bosch and a Detroit fuel system both use a mechanical type injector. Technician B says that a Bosch and a Detroit fuel system both use a port and helix system. Who is correct?

Technician A

Technician B

Both A and B

Neither A nor B

Correct! Wrong!

An operator complains that his engine idle is about 100 RPM more than it was a few days ago, on his Detroit Diesel 8-92 2 cycle engine, what is the likely problem?

injectors out of adjustment

governor gap out of adjustment

one injector stuck in the full fuel position

all of the above

Correct! Wrong!

Which of the following system would control the volume for fuel injection by modifying and controlling pressures within the low pressure supply system relative to engine rpm?

pressure timed

port and helix

sleeve metering

distributor

Correct! Wrong!

Technician A says that a Cummins engine operational timing may adjusted by the use of an offset key on the camshaft. Technician B says that a Cummins engine may be timed by adding or subtracting shims or gaskets from under the cam follower housing covers. Who is correct?

Technician A

Technician B

Both A and B

Neither A nor B

Correct! Wrong!

The term hydraulic governor refers to a governor in which the:

the governor spring and flyweights are counter are counter-balanced by a spool valve

governor speed sensing is aided and balanced by internal oil pressure

high idle is controlled hydraulically

peak torque is controlled by fuel pressure

Correct! Wrong!

On some distributor type fuel systems, timing may be adjusted by:

injector height adjustment

metering valve adjustment.

rotating the fuel pump at its mounting

timing may not be altered

Correct! Wrong!

The metering valve in a cam and plunger distributor type fuel pump controls the amount of ____________ within the pumping element prior to injection.

low pressure fuel

high pressure fuel

high and low pressure fuel

fuel pressure for timing advance

Correct! Wrong!

In a distributor type fuel pump, the cam ring and plungers produce _______________ sent to the injectors.

low pressure fuel

high pressure fuel

high fuel volume

low fuel volume

Correct! Wrong!

The governor on a cam and plunger distributor type fuel system controls the:

racks

metering valve

delivery valve

cam ring

Correct! Wrong!

In a cam plunger distributor type fuel pump, a hydraulically actuated plunger and counter-balancing spring, automatically moves the ______________ back and forth with changing engine speeds, to alter the injection timing advance.

metering valve

cam ring

rollers and plungers.

charging ring

Correct! Wrong!

Before removing a fuel injection pump, you must locate the engine and injection pump for timing and position so that the injection pump can be easily reinstalled in the correct position.

True

False

Correct! Wrong!

To locate a faulty injector on a Cummins PT injection system you should:

loosen the lines at a time and listen for a change in engine performance

hold each injector on its seat and listen for a change in engine performance

loosen the injector adjusting screw locknut and back out the injector while listening to the engine

open the bleed line on each injector and listen for a change in engine performance

Correct! Wrong!

When servicing injectors, you should always remember to:

clean the parts in new fuel only

never interchange plungers and barrels

test them for operation before and after cleaning

all of the above

Correct! Wrong!

If a back-hoe operator sets the engine at 1500 RPM, and a small load is applied to the engine, the variable speed governor will:

drop off substantially and return to set RPM

fall to an idle

maintain speed within the droop adjustment setting

surge to a higher RPM and return to set RPM

Correct! Wrong!

Pintle type fuel injection nozzles are used with:

direct injection

pre-combustion chambers

electronic fuel injection

two stroke cycle engines

Correct! Wrong!

Caterpillar capsule type injectors are adjusted:

on the VS mark

at TDC

at the factory

when the exhaust valves are open

Correct! Wrong!

What engine performance measurement is found by using the following formula: Torque x RPM divided by 5252.

torque

horsepower

mean effective pressure

volumetric efficiency

Correct! Wrong!

A port and helix fuel injection pump using plungers with upper helices would have injection timing with a:

variable beginning

variable beginning and ending

constant beginning

variable ending

Correct! Wrong!

Technician A says that a fuel system must supply the correct quantity of fuel and time the fuel delivery. Technician B says that a fuel system must control the delivery rate and distribute the fuel evenly into the cylinder. Who is correct?

Technician A

Technician B

Both A and B

Neither A nor B

Correct! Wrong!

On a test bench, when a technician adjusts a fuel pump so that the beginning of injection event occurs exactly the correct number of degrees apart, he is said to be ________________ the fuel pump.

calibrating

timing

phasing

metering

Correct! Wrong!

An automatic timing advance mechanism varies injection timing in relation to:

engine load

engine speed

throttle position

governor action

Correct! Wrong!

A governor that has highly controlled speed droop is known as a(n) ______________ governor.

On an engine equipped with a mechanical diesel fuel system, when an operator moves the throttle through the speed ranges, he is altering the governor''s.

On a fuel injection pump utilizing the port and helix system, what position the control edge of the helix for the fuel delivery volume?

On an in-line fuel injection pump utilizing the port and helix system, what tries to maintain system line pressure for a rapid rise and fall of injection pressures?

Technician A says that a limiting speed governor attempts to keep the engine RPM at nearly constant even rate even though the load on the engine may change. Technician B says that the limitiing speed governor will control minimum engine RPM. Who is correct?

What controls the maximum pressure in a high pressure injector fuel line?

When a technician adjusts all the plungers so that they repeatedly produce the exact quantity of fuel, he is said to be ______________ the fuel pump.

On a port and helix fuel pump, when the rack rotates the plunger so that the vertical groove is aligned with the fill port, the pump is said to be in the:

On a port and helix fuel pump system, when the rack rotates the plunger so that the narrowest part of the helix is aligned with the fill/spill ports, the pump is said to be in the:

Injection nozzles that open with the needle valve moving away from the combustion chamber are said to be:

When working with injection nozzles, you should:

When bench testing a set of high pressure injection nozzles. Technician A says that when checking injection nozzles you should check the cracking pressures and forward leakage. Technician B says that you should check the spray pattern and back leakage. Who is correct?

A high pressure fuel injection pump that uses a rack to move a fuel volume control device up and down on the outside of the injection plunger and barrel is known as a _____________ type fuel pump.

If the device mentioned in the previous question were to be moved all the way up, the fuel pump would be in the ____________ position.

A mechanical governor operates on the principle of:

When spill timing a fuel injection pump using the port closing method you would be dealing with a pump having helices with:

When mounting a fuel injection pump to an engine and adjusting the fuel pump drive so that pins will enter respective holes in the flywheel and fuel pump, you are said to be _______________ the fuel pump to the engine.

On a diesel injected engine, if a delivery valve does not seat properly, the engine would:

Technician A says that a fuel injection pump with port and helix system uses a mechanical actuated injector. Technician B says that a distributor type fuel system uses a hydraulically actuated injector. Who is correct?

What will occur if the cracking pressure in a high pressure nozzle is too low?

The most common injection nozzle used with direct injection is the:

The amount of RPM fluctuation from maximum RPM no load to maximum RPM full load is known as:

A fuel pressure gauge test on an engine may indicate:

On a diesel fuel system, when the governor flyweights extend, they change spring tension to move the rack to a ____________ fuel position.

On a fuel injection pump system, what is the purpose of the restricted fitting in the return fuel line at the outlet of the fuel pump?

Which fuel injector type is used by Detroit 2 cycle diesels and Cummins PT injection systems and others?

Injector timing is done on a Detroit Diesel unit injectors by:

What is the purpose of a buffer spring in an engine governor?

What will be the effect if injector plungers are set higher than specifications in a Detroit Diesel 2 cycle engine?

Technician A says that a Bosch and a Detroit fuel system both use a mechanical type injector. Technician B says that a Bosch and a Detroit fuel system both use a port and helix system. Who is correct?

An operator complains that his engine idle is about 100 RPM more than it was a few days ago, on his Detroit Diesel 8-92 2 cycle engine, what is the likely problem?

Which of the following system would control the volume for fuel injection by modifying and controlling pressures within the low pressure supply system relative to engine rpm?

Technician A says that a Cummins engine operational timing may adjusted by the use of an offset key on the camshaft. Technician B says that a Cummins engine may be timed by adding or subtracting shims or gaskets from under the cam follower housing covers. Who is correct?

The term hydraulic governor refers to a governor in which the:

On some distributor type fuel systems, timing may be adjusted by:

The metering valve in a cam and plunger distributor type fuel pump controls the amount of ____________ within the pumping element prior to injection.

In a distributor type fuel pump, the cam ring and plungers produce _______________ sent to the injectors.

The governor on a cam and plunger distributor type fuel system controls the:

In a cam plunger distributor type fuel pump, a hydraulically actuated plunger and counter-balancing spring, automatically moves the ______________ back and forth with changing engine speeds, to alter the injection timing advance.

Before removing a fuel injection pump, you must locate the engine and injection pump for timing and position so that the injection pump can be easily reinstalled in the correct position.

To locate a faulty injector on a Cummins PT injection system you should:

When servicing injectors, you should always remember to:

If a back-hoe operator sets the engine at 1500 RPM, and a small load is applied to the engine, the variable speed governor will:

Pintle type fuel injection nozzles are used with:

Caterpillar capsule type injectors are adjusted:

What engine performance measurement is found by using the following formula: Torque x RPM divided by 5252.

A port and helix fuel injection pump using plungers with upper helices would have injection timing with a:

Technician A says that a fuel system must supply the correct quantity of fuel and time the fuel delivery. Technician B says that a fuel system must control the delivery rate and distribute the fuel evenly into the cylinder. Who is correct?

On a test bench, when a technician adjusts a fuel pump so that the beginning of injection event occurs exactly the correct number of degrees apart, he is said to be ________________ the fuel pump.

An automatic timing advance mechanism varies injection timing in relation to:

Success!

Heavy-Duty Mechanic - Trucks & Equipment