190203f Basic Diesel And Fuel System Testing And Adjusting

Question 0

What are the effects if injector nozzles are not operating properly

Answer 0

Hard starting
Rough idle
Low power
White or /black smoke

Question 1

What to operating conditions may affect the tuneup interval for an engine

Answer 1

The type of engine and the application

Question 2

How would you do a cylinder balance test ( injector cut out)

Answer 2

By momentarily loosening ( cracking) fuel injector line connection

Question 3

By useing a infrared thermometer to check for misfiring where should you check at ?
and what is maximum temperature drop?

Answer 3

At exhaust port

No more than 50 degres

Question 4

Dynamometer are used for ?

Answer 4

engine performance testing, diagnosis, trouble shooting and break-in after rebuild

Question 6

With kind of engine conditions are you able diagnose with a dynamometer ?

Answer 6

misfiring cylinders
operational noise
vibration
crankcase pressure (blowby)

Question 7

Two operating conditions that may affect the tune-up interval for an engine are…

Answer 7

Type of engine load

Application

Question 8

What are three benefits of a properly tuned engine?

Answer 8

Low emissions
Most efficient engine operation
Maintained horsepower

Question 9

List three conditions of an engine that may require a tune up

Answer 9

Mechanisms have been disturbed for repairs
Poor engine operation
Part of scheduled maintanence

Question 10

How does excessive valve clearance affect an engine?

Answer 10

It causes retarded timing and reduced valve opening, causing poor engine performance

Question 11

When you perform adjustments to a governor, what condition must the engine be in?

Answer 11

Warmed up to operating temperature

Question 12

What should you check before performing governor adjustments?

Answer 12

You should check the throttle linkage condition for play and proper adjustment

Question 13

True or false. On a diesel engine, a timing light is triggered by an electrical pulse generated in the injector line.

Answer 13

False. It operates on the high pressure pulse of the line expanding during each injection.

Question 14

To isolate a faulty fuel injector on a running engine, momentarily crack the line on each injector and note the RPM drop, OR…

Answer 14

Check the temperature drop between the exhaust ports.

Question 15

True or False. The fuel injector needle opening pressure cannot be adjusted on any type of injector. If incorrect, the injector must be changed out.

Answer 15

False. On most hydraulic injectors you can adjust opening pressure by installing shims or via the adjustment screw.

Question 16

How do you check for fuel injector needle seat - to - face leakage? (dribble)

Answer 16

Watch for fuel seepage at the nozzle tip while the injector is under pressure.

Question 17

True or False. When you test a multi-hole fuel injector, the spray pattern is evenly generated by all of the spray hole orifices in the nozzle.

Answer 17

True

Question 18

What does a dynamometer do?

Answer 18

It absorbs and measures the power output of an engine. It allows you to test performance and simulate load conditions on the engine.

Question 19

What are the three basic components a Dynamometer

Answer 19

A power absorption device (load cell), a load control and a torque measuring device

Question 20

What are the two functions water has in a water brake type dynamometer.

Answer 20

Cooling and load control

Question 21

List three engine/vehicle sources from which dynamometers can measure power

Answer 21

Off the engines flywheel, from the vehicles rear wheels, off the PTO shaft of a tractor

Question 22

What is the formula for horsepower

Answer 22

Torque times RPM over 5252

Question 23

What are three things you should do when using a dynamometer regarding personal safety

Answer 23

Wear PPE, avoid rotating equipment and tie up longhair

Question 24

True or false. A vehicle on a chassis type dynamometer must be placed squarely on the rollers and be properly chained and blocked before the vehicle is operated

Answer 24

True

Question 25

What’s the proper procedure for breaking in an engine on a dynamometer when bringing an engine up to operating temperature

Answer 25

Warm the engine up at Idle and get to operating temperature before applying the load

Question 26

What are the four basic steps for performance engine or fuel system diagnosis

Answer 26

Gather relevant information, perform operation test to verify, determine possible causes and perform test based on result of diagnosis

Question 27

List five problems that could cause a hard starting?

Answer 27

1. low fuel level
2. restricted inlet
3. cracked or loose inlet pipe or hose
4. plugged filter
5. fuel system drain back to tank on shut down