单选题The degree to which the viscosity of an oil will change with a change in temperature is indicated by the （）.A weight designationB viscosity indexC pour pointD thermal change value

Oil oxidation as a result of excessively high lube oil temperature, is harmful to a diesel engine Because

A.oil foaming will always occur

B.large quantities of oil are consumed

C.lube oil viscosity is always decreased

D.corrosive by-products are usually formed

Which of the following statements is correct regarding an oil with a high viscosity index?

A.A large change of viscosity occurs with a minor change in temperature

B.No change in viscosity occurs with any change in temperature

C.Very little change in viscosity occurs with a significant change in temperature

D.The viscosity of the oil increases with an increase in temperature

Which factor determines the ring dam size for a fuel oil, tubular bowl type, centrifugal purifier?

A.The viscosity of the fuel.

B.The quantity of water to be removed from the fuel.

C.The specific gravity of the fuel.

D.The quantity of dirt to be removed from the fuel.

_______can cause oil flow from water outlet of the oil purifier.

A.Oil inlet valve opening too quickly

B.Oil temperature little higher than normal

C.Diameter of gravity disc too small

D.Viscosity of oil little lower than normal

Which of the following problems may be encountered by using an oil having a viscosity higher than that specified for an operating hydraulic system?

A.External seal leakage

B.Hunting due to fast response

C.Hydraulic oil film breakdown

D.Increased power consumption

A large change in ambient temperature, or using an oil of a viscosity different than the one recommended by the manufacturer in a mechanical hydraulic governor, will result in the need to adjust the

A.pilot valve opening

B.compensating needle valve

C.compensating spring tension

D.accumulator spring tension