A.warm-up allows the hydraulic system to become charged with oil
B.warm-up allows the relief valves to be properly tested
C.hydraulic strainers operate only during the warm-up period
D.hydraulic fluid must be at the proper viscosity
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A.are exposed to a vacuum
B.come in contact with extremely hot surfaces
C.are reduced in temperature to just above the pour point
D.become extremely agitated or aerated
A.weight
B.internal friction
C.demulsibility
A.Extensive centrifuging
B.Wax content
C.Water content
D.Acid content
A.Viscosity will increase as temperature increases
B.Viscosity is a measure of a fluid s internal resistance to flow
C.Viscosity will decrease as temperature decreases
D.Viscosity is not dependent on temperature
A.the manual trick wheel is engaged for steering
B.the variable stroke pump is off stroke
C.a rudder order is given by the control system
D.an electric power system failure occurs at the steering gear
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If the thermal bulb of an expansion valve is incorrectly placed at the center of the coil instead of the end, it will （）.
When a refrigeration compressor has developed a high head pressure as a result of a refrigerant overcharge, you should （）.
The usual symptoms of cavitation in a centrifugal pump is （）.
The major source of chemical contaminants in hydraulic fluid is （）.
An internal bypass is provided on some hydraulic system suction strainers to help reduce the possibility of （）.
The output volume of a positive fixed displacement pump can be changed only by （）.
A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by （）.
A grease gun is generally used to lubricate a （）.
Which of the following problems could cause the high pressure cutout switch to shut down the compressor in a refrigeration system?（）
The rate of heat transfer between the hot and cold fluids passing through a shell-and-tube type heat exchanger will （）.