overcooling
poor cooling
overloading
unloading
第1题：
_____ allows for expansion and water make up in the water cooling system.
A.A top tank
B.A head tank
C.A head valve
D.A drain tank
第2题：
Why is it necessary to have routine testing of the cooling water?
A.To ensure that the proper residuals of treatment chemicals, as specified, are maintained all time
B.To trace leakage in the cooling water system
C.It is not necessary
D.To detect the presence of contaminants in the water that may be injurious to the cooling system
第3题：
What is head tank in the closed cooling water system used for?
A.for the release of air from the cooling water
B.providing expansion room for heated cooling water
C.a place for implementing water and water treatment agent
D.all of the above
第4题：
air binding of the engine cooling system
a cracked water cooled exhaust manifold
blockage in the heat exchanger
faulty operation of the thermostat
第5题：
fresh water expansion tank
sea water expansion tank
thermostatic expansion valve
jacket water cooler accumulator
第6题：
High diesel engine cooling water temperatures can be caused by ______.
A.air in the cooling system
B.an overhauled water pump
C.correct amount of coolant
D.no air in the cooling system
第7题：
An open vent in the cooling system
A fouled sea chest
A restricted water passage in the engine
Air entrained in the cooling water
第8题：
If the coolant temperature of a closed cooling water system for a diesel enginegradually increases, the trouble usually is( ).
A.a broken shaft on the freshwater pump
B.an excessive accumulation of scale in the heat exchanger
C.an incorrect thermostatic element operating range
D.lube oil in the cooling water
第9题：
steering
timing
turning
running
第10题：
discharge side of the centrifugal pump
suction side of the centrifugal pump
the lowest point of the cooling water system
inlet of the main engine