Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Diesel Fuel Injection Systems > 190203d Fuel System Service > Flashcards

190203d Fuel System Service Flashcards

0
Q

So far the only highway vehicle with a final stage filter is a Mack truck. What are four things you can list about a final stage filter?

A

Extremely fine filtration, located just before injection pump, subject to positive pressure and used only with certain types of pumps (single plunger distributor type)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

Fuel filters are rated according to their ability to stop certain sized particles measured in

A 
Microns
One grain of table salt is 100 µm
One strand of human hair 70 µm
Smallest particle visible to the human eye 40 µm
One grain of talcum powder 10 µm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are three things you can say about a transfer pump in their operation

A

They are all relatively low pressure pump, they move fuel from the fuel tank to the injection pump or unit injectors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are five basic types of fuel transfer pumps

A

Diaphragm, plunger, hand primer, gear and vane/blade.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Diaphragm pumps are used by some manufacturers as a…

A

Lift pump to provide a steady volume of fuel to a vane type transfer pump(in integral part of the injection pump)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are two methods of operating a diaphragm pump

A

Off the engine or injection pump camshaft

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

True or false. Diaphragm pumps will work with the cam turning in either direction.

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the self regulating mechanism in a diaphragm pump.

A

Diaphragm spring tension controls maximum fuel pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What pressure to diaphragm pumps normally operate at (max)

A

Output usually limited to 10 psi maximum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Does a diaphragm pump produce a smooth or pulsating output

A

Pulsating

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

True or false. Diaphragm pumps may include a sediment and/or water separator?

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

If a diaphragm pump has a built-in hand primer and does not seem to be priming what may be the issue

A

The lever inside the engine may be high on the camshaft eccentric. You may need to rotate engine to bring the lever down

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Fuel flow through the plunger type pump is controlled by what

A

A set of check valves and spring pressure will determine the fuel pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Name the components of a plunger pump body

A

Roller tappet, plunger push rod, plunger, plunger spring, spring cap

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are hand primer pumps used for

A

To manually bleed primary fuel system after air is admitted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

True or false

Are all fuel systems equipped with hand primers

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What must be done with the plunger when pumping process is completed

A

Make sure to seat the plunger and lock the shaft to keep foreign material out

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where can a gear type pump be mounted

A

Integral part of a fuel pump assembly or mounted and driven by the engine gear train

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

As a get pump rotates where dose the low pressure or vacuum develop

A

Inlet side

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

True or false

Gear pumps must have a set screw to slow rotation when maximum pressure is reached

A

False.

Pressure relief is used

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Vane or Type pumps are commonly used in single or opposed plunger distributor type fuel injection pumps as an integral transfer pump

A

Blade

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

A operation of a vane type pump are

A

May be assembled for bi-directional rotion
Will produce high pressure
A positive displacement
Smooth output with limit pulsation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Fuel filters filter what size partials ?

A

Microns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

List four kind of basic fuel filters.

A
  1. screen / strainer
  2. surface
  3. depth
  4. edge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How do surface filters remove contaminates from the fuel ?

A

By not allowing partials larger than the filter medium to pass through it.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Three common filter classifications are…

A
  1. primary
  2. secondary
  3. final stage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Fuel system contamination happens most often when ?

A

Refuelling or fuel filter maintenance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Fuel drained from the system during filter maintenance should be…

A

Disposed of in an environmentally friendly manner.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

During new filter installation what two things can be done to prevent system contamination ?

A
  1. use the system hand pump to fill the new installed empty filter.
  2. fill new filter with clean filtered fuel before installation.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

After installation of a new fuel filter the engine runs rough, why ?

A

Air in the fuel system.

30
Q

Five basic types of fuel transfer pumps are?

A
  1. diaphragm
  2. plunger
  3. hand primer
  4. gear
  5. vane or blade.
31
Q

Diaphragm & plunger pumps are operated by ?

A

An eccentric on the engine or fuel injection pumps camshaft.

32
Q

Gear & vane ( blade ) style pumps are positive displacement. So they must have a to control max system pressure.

A

Pressure relief valve

33
Q

Why must a hand pump be seated & locked ( threaded ) in place ?

A

To prevent contamination of the fuel system & prevent fuel leakage while the engine is running.

34
Q

Why don’t diaphragm & plunger pumps need a pressure relief valve ?

A

Spring pressure limits the max pressure these pumps can develop.

35
Q

Gear & vane (blade) pumps are alike, why ?

A

Both have a specific direction of rotation.

36
Q

Before testing or diagnosing any fuel system what first should be checked ?

A

Fuel tank level(s)

37
Q

The correct amount of fuel flow is important to ensure?

A

A sufficient volume of fuel for injection pump and sufficient cooling of system components

38
Q

What is a special tool for testing flow in a system called?

A

Flowmeter

39
Q

Low fuel volume could be the result of?

A

High inlet restriction, restricted fuel line, a plugged fuel filter, a worn transfer pump

40
Q

Air in the fuel system could be the result of?

A

A cracked or broken fuel tank strand pipe, loose fit fittings, cracked fuel lines or hoses, missing gaskets or O-rings in the primary fuel filter assembly

41
Q

For every 5.5°C (10°F) above 37.8°C (100°F) engine power decreases by how much?

A

1%

42
Q

Diaphragm pumps are inexpensive dependable units that can tolerate _______ and _____ with very little damage.

A

Abrasives and water

43
Q

Plunger type pumps have closely fitted components that will not tolerate _______ or _______ In a fuel system.

A

Abrasive material or water

44
Q

List five problems that could cause hard starting

A

Low fuel level, restricted inlet (plugged), cracked or loose inlet pipes or hoses, plugged filter before pump and fuel system draining back to tank after shutdown

45
Q

Why select fuel system test gauges that ranges twice the pressure being measured

A

To ensure accurate test readings and protect the gauge from possible damage

46
Q

What are you testing for when you install a gauge between the fuel supply tank and the transfer pump inlet on running engine

A

You are checking inlet restriction

47
Q

What are the two basic methods for testing fuel system volume

A

Measure the volume of fuel flow with the engine running at a specific RPM and measure the output volume of the fuel pump while the engine is cranking

48
Q

What are four problems that could cause low fuel system volume

A

Hi inlet restriction,restricted fuel lines, a plugged fuel filter, a worn transfer pump

49
Q

What units of measurement are commonly used when testing inlet restriction

A

Inches of mercury or millimeters of mercury

50
Q

How do you test fuel pressure

A

On a running engine install a gauge on the outlet side of the transfer pump after the secondary filter

51
Q

What are four possible causes of air entering the fuel system

A

Cracked or broken fuel tank standpipe, loose fittings, cracked fuel lines or hoses and missing gaskets or O-rings in the primary fuel filter assembly

52
Q

Sealed feel pump should not be disassembled unless you have what three things

A

Proper training, a clean environment and the correct tools

53
Q

Fuel leaking from the vent all of the diaphragm type pump would be caused by

A

Torn or leaking diaphragm

54
Q

A plunger type pump with the week or broken plunger spring would have

A

Low volume or pressure

55
Q

It’s a gear or vane pump had a broken pressure relief spring what effect with this have on the fuel system

A

A broken pressure relief spring would cause low fuel pressure

56
Q

What three clearances should be checked when inspecting a gear type transfer pump

A

Gear to gear, gear to pump body, gear to cover

57
Q

What five areas of a vane type pump should be checked for wear

A

end and the side of the vanes, rotor slots, inside surface of the liner and endplate or cover

58
Q

7 test that can be done on the fuel supply system, these tests can reveal engine problems as?

A

Hard starting
Stalling
Rough running
Low power

59
Q

Symptoms that could cause a Hard Start could be

A 
Low fuel level
Restricted inlet
Plugged fliter (before pump)
Cracked or lose inlet pipes
Fuel draning back to tank after shut down
60
Q

Symptoms that could relate to engine stalling are?

A

Low fuel level
Restricted inlet
Cracked or lose inlet pipeing
Plugged fuel filter, ( before or after pump)

61
Q

A symptom of a rough running could be?

A

Low fuel level

Aerated filter

62
Q

Symptom of a engine with low power could be

A 
Low fuel level
Low fuel pressure
Low fuel volume
High inlet restrictions 
Plugged fuel filters
Restriction in fuel lines
Poor fuel quality
63
Q

When testing the fuel system, for maximum accuracy gagues should be selected with a range no greater than?

A

Twice the pressure being measured

64
Q

To test inlet restriction install a ______

As close as possabile to the _________

A

Vacuum gauge

Transfer pump inlet

65
Q

A high inlet restriction could be the result of?

A

Plugged tank vent
Restricted fuel lines
Plugged filter before the pump

66
Q

When the timing pin in the front gear cover it fits into a hole in the cam shaft drive gear, when timing pin is installed , the engine has to be at?

A

At TDC on the compression stroke.

67
Q

2 company’s that manufacture opposed plunger pumps are?

A

Stanadyne (roosa master) and Lucas (CAV)

68
Q

Oppposed plunger pumps are also called?

A

Rotary or distributor, cause the injector out lets are arranged to specific number of degrees apart in a circular pattern according to firing order.

69
Q

Identify three factors that affect the operation of the fuel injector and have a negative influence on fuel injectors service life.

A

water
heat
dirt

70
Q

List three clearance that should be checked when inspecting a gear type transfer pump?

A

gear to gear clearance
gear to pump body clearance
gear to body cover clearance

71
Q

List five areas of a vane pump that should be checked for wear?

A 
ends of the vanes 
sides of the vanes
rotor slots
inside surface of the ring
end plate or cover
72
Q

What is the approximate transfer pressure for a EUP system?

A

70 psi

73
Q

both gear and vane transfer pumps are positive displacement and must have a __________ to control maximum fuel system pressure.

A

relief valve

Diesel Fuel Injection Systems (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions