单选题Dirt lodged on the nozzle valve seat of a fuel injection nozzle will cause（）Aerosion and cratering of the nozzle orificesBfuel leakage into the nozzle drain lineCfuel leakage before and after injectionDinsufficient fuel delivery though that nozzle
单选题
Dirt lodged on the nozzle valve seat of a fuel injection nozzle will cause（）
A
erosion and cratering of the nozzle orifices
B
fuel leakage into the nozzle drain line
C
fuel leakage before and after injection
D
insufficient fuel delivery though that nozzle
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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
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