单选题If the plunger or barrel of a fuel injection jerk pump becomes damaged,（）Aonly the replacement of the entire pump would be acceptableBthe injection pump and injection nozzle must be replacedCeither the barrel or plunger must be replacedDthe barrel and plunger must be replaced as a unit
单选题
If the plunger or barrel of a fuel injection jerk pump becomes damaged,（）
A
only the replacement of the entire pump would be acceptable
B
the injection pump and injection nozzle must be replaced
C
either the barrel or plunger must be replaced
D
the barrel and plunger must be replaced as a unit
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相关考题：
The plunger in a jerk pump is rotated until the release port is uncovered If the port remains uncovered all of the time, which of the listed operations will occur?A.No fuel will be deliveredB.The maximum effective stroke will be attainedC.The fuel delivered to the cylinder will be excessiveD.The injection nozzle will overheat and carbonize
Which of the following problems is the main source of fuel pump and injection system malfunctions?A.Improper lubricationB.Air in the fuel systemC.Coated fuel linesD.Excessive vibration
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The amount of fuel delivered by a helical plunger fuel injection pump is controlled by ______.A.varying the pump discharge pressureB.varying the pump return pressureC.rotation of the pump plungerD.rotation of the pump barrel
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