Diesel/Heavy Equipment Tech-Cooling Systems

A chemical that when added to water, lowers the freezing point and raises the boiling point is termed a:

• Antifreeze

• Dex-cool

• Coolant

• Permanent Antifreeze

Increasing the operating pressure of a cooling system will:

• Lower the freezing point

• Raise the boiling point

• Reduce corrosion

• Improve thermostat operation

Technician A states that antifreeze can be disposed of by pouring it down a floor drain if diluted 50% with water. Technician B states that it is safe to remove a radiator cap 10 minutes after shutting down the engine. Who is correct?

• Technician A only

• Technician B only

• Both Technicians A and B

• Neither Technician A or B

Engine coolant comes in all of the following colors except:

• Green

• Gold

• Red

• Blue

Technician A states that all popular coolants are chemically compatible. Technician B states that it is best to use the manufacturers recommended coolant whenever possible. Who is correct?

• Technician A only

• Technician B only

• Both Technicians A and B

• Neither Technicians A or B

Engine Coolant can be tested for all but one of the following:

• Lubricity

• Nitrate level

• Molybate level

• Freeze point

Technician A states that DCA2 coolant additive includes Molybdate to protect against corrosion. Technician B states that DCA4 includes high levels of Nitrates to protect against liner cavitation pitting. Who is correct?

• Technician A only

• Technician B only

• Both Technicians A and B

• Neither Technician A or B

All of the following are methods for testing engine coolant for freeze point except:

• Litmus paper strips

• Specific gravity float type

• Test strips

• Refractometer

Technician A states that the heated coolant leaved the engine through the upper radiator hose. Technician B states that cooled coolant enters the engine through the thermostat. Who is correct?

• Technician A only

• Technician B only

• Both Technician A and B

• Neither Technician A or B

Technician A states that the coolant pump is a positive displacement type pump. Technician B states that the coolant flows through the engine from the bottom of the engine toward the top. Who is correct??

• Technician A

• Technician B

• Both Technicians A and B

• Neither Technician A or B