Deck 16: Diesel Engine Run- in and Performance Testing

Question 1

What is another way of saying engine longevity?

A) engine length
B) expected engine life
C) engine serviceability
D) engine warranty period

Answer 1

expected engine life

Question 2

What is the preferred run-in method for a highway diesel engine after an overhaul?

A) do not exceed 50 mph for the first 1000 miles
B) do not run at full load for the first 500 miles
C) full load operation on a dynamometer
D) highway road test

Answer 2

full load operation on a dynamometer

Question 3

When a truck diesel engine is run in a linehaul application, how is the truck being run?

A) highway, terminal to terminal
B) vocational
C) LTL, pick-up and delivery
D) construction hauling

Answer 3

highway, terminal to terminal

Question 4

What is the preferred method of priming an engine lubrication system with engine oil?

A) Hand prime the turbocharger
B) Hand prime the oil filters
C) Hand prime the oil cooler
D) Use a prelubricator

Question 5

When instructed to hand prime a full flow oil filter, which of the following procedures is correct?

A) immerse filter in fresh oil
B) fill the filter with clean engine oil
C) silicone the filter sealing gasket
D) purge air at the filter pad

Question 6

In order to purge air from a diesel engine cooling system after reconditioning, which of the following is recommended?

A) separate the upper radiator hose
B) remove the radiator drain plug
C) remove the thermostat housing
D) vent circuit by cracking a water manifold plug

Question 7

Which of the following steps is recommended following a diesel engine rebuild to check for leaks before allowing it to start?

A) no-fuel crank for 15 seconds
B) no-fuel crank for 2 minutes
C) charge intake with ether
D) pressure test cooling system

Question 8

Which of the following methods of priming a diesel fuel system is NOT recommended?

A) crack fitting at fuel transfer pump outlet
B) loosen fitting at secondary filter outlet
C) purge fuel water separator
D) pressurize fuel tank with shop air

Question 9

Which of the following values represents a typical maximum oil temperature specification in a diesel engine?

A) 195 degrees Fahrenheit
B) 225 degrees Fahrenheit
C) 240 degrees Fahrenheit
D) 275 degrees Fahrenheit

Question 10

Which of the following values represents a typical maximum diesel engine coolant temperature specification?

A) 180 degrees Fahrenheit
B) 195 degrees Fahrenheit
C) 200 degrees Fahrenheit
D) 250 degrees Fahrenheit

Question 11

Which type of dynamometer functions similarly to an electric motor turned in reverse?

A) hydromechanical
B) mechanical
C) electronic
D) Electric motor

Question 12

What is the hydraulic medium used in a typical truck chassis dynamometer?

A) water
B) hydraulic oil
C) transmission oil
D) engine oil

Question 13

When installing a tandem drive axle truck on a chassis dynamometer, which wheels must be wedged and chained?

A) front axle wheels
B) forward drive axle only
C) rear drive axle only
D) both drive axles

Question 14

When running a truck on a chassis dynamometer, what gear ratio should be selected for most of the test sequence?

A) the lowest gear
B) the highest gear
C) 1:1 ratio
D) highest gear in low range

Question 15

When a double roller type chassis dynamometer is used to test a truck, what is the maximum speed difference permissible between the rear axles?

A) 0 mph
B) 5 mph
C) 10 mph
D) 15 mph

Question 16

When using a dynamometer to break in a set of piston rings on a rebuilt diesel engine, what is the minimum period the engine should be run at maximum power at rpms within its torque rise profile?

A) five minutes
B) ten minutes
C) twenty minutes
D) forty minutes

Question 17

Following a full load dynamometer test, what is the minimum period the engine should be run at idle speed before shut down?

A) five minutes
B) ten minutes
C) twenty minutes
D) forty minutes

Question 18

What percentage of brake horsepower is produced at a set of tandem axle drive wheels compared with brake horsepower produced at the flywheel?

A) 50 - 55 percent
B) 80 - 85 percent
C) 100 percent
D) 120 - 125 percent

Question 19

What is the main safety reason that no person should be outside the vehicle in a chassis dynamometer test room during testing?

A) combusted diesel fumes
B) unpleasant odor from tires
C) stones may dislodge from tires
D) high noise level

Question 20

Which of the following is the most important requirement before taking a truck out on a road test?

A) circle test
B) check oil level
C) driver is properly licensed
D) check coolant level

Question 21

When testing a newly reconditioned engine on a chassis dynamometer, what should be done when the maximum coolant temperature is achieved?

A) immediately switch off engine
B) back-off on power and monitor gauge
C) ignore it until the test report is complete
D) immediately shift into neutral

Question 22

When chassis dynamometer testing trucks, which of the following can damage health or cause personal injury?

A) debris thrown from tire treads
B) excessive noise levels
C) fumes from vaporizing tire rubber
D) all of the above

Question 23

Technician A says that recapped tires should never be used when chassis dynamometer testing trucks due to the increased risk of tread separation. Technician B says that when snow lugs are fitted to a truck being dynamometer tested, overheating and erratic performance results. Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 24

When testing a tandem drive axle truck on a double roller chassis dynamometer, what is the maximum acceptable road speed differential between the two drive axles?

A) 5 mph (8 kph)
B) 8 mph (12 kph)
C) 12 mph (20 kph)
D) 20 mph (32 kph)