Cooling Systems Flashcards
Shrouding is used around a fan to:
a. Simply protect the fan blades
b. Increase fan efficiency
c. Reduce the noise of fan operation
d. Make it look neater
b. Increase fan efficiency
A collapsed radiator hose could be a sign that the:
a. Water pump is cavitating
b. Thermostat is opening too quickly
c. Vacuum valve is stuck closed
d. Head gasket is leaking
c. Vacuum valve is stuck closed
When the thermostat is closed, water is circulated through the engine water jacket by means of:
a. A bypass
b. The upper hose
c. The lower hose
d. A restrictor valve
a. A bypass
The reason that a viscous fan clutch uses silicon oil is that its viscosity [blank] as temperature increases.
a. Increases greatly
b. Decreases greatly
c. Stays comparably more stable
d. Does not change at all
a. Increases greatly
The purpose of the bimetal coil spring on the front of a viscous fan clutch is to:
a. Change the oil’s viscosity with temperature
b. Allow the fan to free wheel in hot weather
c. Control the entry of silicon oil to the fan clutch’s working chamber
d. None of the above
c. Control the entry of silicon oil to the fan clutch’s working chamber
The purpose of the radiator pressure cap is to pressurize the cooling system so that the system can be operated:
a. With no danger of radiator collapse
b. Safely at higher temperatures
c. Safely at higher speed
d. Without antifreeze
b. Safely at higher temperatures
The two valves in the pressure cap are the pressure relief valve and the:
a. Blow off valve
b. Vacuum valve
c. Radiator valve
d. Purge valve
b. Vacuum valve
The driving friction provided by a V-belt is on:
a. Both sides of the belt
b. The sides and bottom of the belt
c. The bottom of the belt only
d. The top and bottom of the belt
a. Both sides of the belt
Fan blades are sometimes arranged in an uneven fashion in order to:
a. Improve air circulation
b. Balance the unit
c. Reduce turbulence and noise
d. Equalize the weight distribution
c. Reduce turbulence and noise
How much of the heat energy in the fuel must be handled by the cooling system?
a. 1/4
b. 1/3
c. 1/2
d. 1/10
b. 1/3
Thermostats are usually installed between the:
a. Pump inlet and the radiator
b. Pump outlet and the water jacket
c. Water jacket and the radiator
d. Cylinder head and intake manifold
c. Water jacket and the radiator?
What is the boiling point of water with a 10lbs pressure cap?
a. 106 C (222 F)
b. 111 C (232 F)
c. 117 C (242 F)
d. 122 C (252 F)
c. 117 C (242 F)
Water pumps are usually [blank] type pumps.
a. Positive displacement
b. Centrifugal
c. Piston
d. Vane
b. Centrifugal
A pressurized cooling system not only raises the coolant boiling point, but also:
a. Prevents corrosion build up
b. Aids heat transfer
c. Increase the water pump efficiency
d. Both B and C
c. Increases the water pump efficiency
A closed cooling system is a standard pressurized cooling system the addition of a:
a. Special thermostat and radiator hoses
b. Special radiator cap and thermostat
c. Special radiator cap and coolant recovery tank
d. Locking radiator cap and sealed hose clamps
c. Special radiator cap and coolant recovery tank
The recommended antifreeze / water mixture for best overall cooling system performance is:
a. 20 / 80
b. 30 / 70
c. 50 / 50
d. 60 / 40
c. 50 / 50
The recommended type of antifreeze used for cooling systems is:
a. Ethylene glycol
b. Denatured alcohol
c. Tetra-ethyl lead
d. Methanol
a. Ethylene glycol
A tech states that a thermostat can only cause overheating at freeway speeds but that it can be left out of the engine with no ill effects.
a. True
b. False
b. False
The most likely cause of overheating at highway speeds is:
a. Thermostat stuck open
b. Electric fan not functional
c. Inadequate radiator core capacity
d. Incorrect antifreeze concentration
c. Inadequate radiator core capacity
What is the most likely cause of an engine overheating in city stop and go traffic?
a. Thermostat stuck open
b. Electric fan not functional
c. Inadequate radiator core capacity
d. Incorrect antifreeze concentration
b. Electric fan not functional
Continuous bubbling observed at the radiator filler that stops when the engine is shut off could be a sign that:
a. The head gasket is leaking
b. The coolant is boiling
c. There is a localized hot spot in the cooling system
d. Any of the above
a. The head gasket is leaking
Continuous bubbling observed at the radiator filler that continues after the engine is shut off could be a sign that:
a. The head gasket is leaking
b. The coolant is boiling
c. There is a localized hot spot in the cooling system
d. Any of the above
b. The coolant is boiling