单选题Cracking of a diesel piston crown can result from（）AExcessive piston to liner clearanceBThe underside of the piston crown being excessively dirty lowering the rate of heat transferCFaulty nozzle sprayDAll of the above
单选题
Cracking of a diesel piston crown can result from（）
A
Excessive piston to liner clearance
B
The underside of the piston crown being excessively dirty lowering the rate of heat transfer
C
Faulty nozzle spray
D
All of the above
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