Deck 6: Cooling and Lubrication Circuits

Question 1

What are the benefits of using a water manifold?

A) Lower operating pressures resulting in less system failures.
B) Simplified cooling system with less components.
C) The ability to operate at higher pressures to increase heat transfer.
D) Better coolant distribution resulting in more consistent cylinder temperatures.

Answer 1

D

Question 2

What is a characteristic of a multi-viscosity versus a straight grade engine oil?

A) Performs better over a wider range of temperatures.
B) Performs better in colder temperatures.
C) Performs better at higher temperatures.
D) Higher resistance to flow.

Answer 2

A

Question 3

What is hydrodynamic suspension?

A) Use of engine coolant as a bearing lubricant.
B) A type of chassis suspension.
C) The ability of engine oil to suspend particulates.
D) Floating a shaft on a bed of pressurized flowing oil.

Answer 3

D

Question 4

What are the characteristics of engine oil with a high viscosity index?

A) Loses viscosity more quickly as temperatures rise.
B) Maintains better viscosity as temperatures rise.
C) Tends to thicken as temperature rises.
D) Tends to thin as temperature drops.

Question 5

What is the recommended procedure to tighten an engine oil filter?

A) Tighten the filter until a click is heard.
B) Turn as tight as possible using a standard oil filter wrench.
C) Rotating one-half to a full turn after the gasket makes contact with the filter pad.
D) Torque to a loose fit because oil gaskets expand when heated.

Question 6

What is typical engine oil operating temperature in diesel engines.

A) 210 degC (410 degF)
B) below 60 degC (140 degF)
C) There is no typical temperature it varies widely depending on engine design.
D) 110 degC (230 degF)

Question 7

What is often a primary reference for the engine management software when determining timing and air/fuel ratio.

A) Coolant temperature.
B) Coolant system pressure.
C) Coolant level.
D) Coolant flow rate.

Question 8

What procedure is required when using silicone-compound coolant hoses?

A) More frequent replacement.
B) Use of specially formulated coolants.
C) Should only be installed using quick-couple hose connectors.
D) Use of specialized clamps torqued to the OEM specifications.

Question 9

How does scaling effect cooling systems?

A) It causes operating temperature fluctuations.
B) It has no effect on the cooling system.
C) Increases heat transfer causing low operating temperatures.
D) Limits heat transfer.

Question 10

When does boundary lubrication occur?

A) When distances between metal surfaces are wider.
B) Only between two dissimilar metal surfaces.
C) When distances between metal surfaces are narrow.
D) When the primary function of the lubrication is cooling.

Question 11

In a maintenance inspection routine, when should fan belts be replaced?

A) Every time any engine maintenance is performed.
B) When glazed, cracked or nicked.
C) Only when fully worn out.
D) When belts squeal or become noisy.

Question 12

Technician A states that a oil pressure regulating valve can be adjusted by setting the spring tension with shims or an adjustment screw. Technician B states that color coded replacement springs are used to adjust oil pressure regulating valves. Which technician is correct?

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

Question 13

By how much does the coolant boiling point change for each 1psi rise in pressure?

A) Minus 30 degF
B) Plus 30 degF
C) Minus 3 degF
D) Plus 3 degF

Question 14

Which color of antifreeze is approved for light duty diesels?

A) Only green or yellow colored.
B) Any color, antifreeze color is meaningless.
C) Only clear antifreeze should be used.
D) Any color except blue and yellow.

Question 15

What are three radiator flow routing patterns?

A) Downflow, crossflow and double pass.
B) Single, split and multi-flow.
C) Downflow, crossflow and upflow.
D) Gravity, pressure and suction flow.

Question 16

What is indicated by a milky sludge collecting in the bottom of the oil pan?

A) Degraded engine oil from overuse.
B) Internal engine coolant leak.
C) Nothing, this is a normal condition.
D) Coolant leak into the combustion chamber.

Question 17

What type of engines is high-silicate antifreeze recommended for?

A) Engines with aluminum heads and/or cylinder blocks.
B) Both aluminum and cast iron engines.
C) It should not be used in any diesel engines.
D) Engines with cast iron blocks and cylinder heads.

Question 18

At which location will coolant usually boil first in an overheated engine?

A) At the point in the cooling system with the highest pressure.
B) Outlet (pressure side) of the water pump.
C) Inlet (suction side) of the water pump.
D) In the radiator.

Question 19

What does a collapsed radiator hose indicate?

A) Scaling in the cooling system.
B) Radiator cap malfunction.
C) Overheating condition.
D) Blockage in the cooling system.

Question 20

When reconditioning a coolant pump, what critical specification effects pumping efficiency.

A) Impeller blade thickness.
B) Amount of allowed scale buildup on the impeller.
C) Impeller-to-housing clearance.
D) Impeller shaft wear.

Question 21

Technician A states that oil cooler bundles can be tested using a vacuum adapter. Technician B states that oil cooler bundles can be tested using regulated air pressure.

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