单项选择题
A.the stem and heads are made of different material B.low-alloy steel is used throughout C.a replaceable valve disk is welded to the head D.the self-centering action comes from motion of the valve stem in the guide
If scavenge box should be hot, （）would occur.A.seized p...
单项选择题If scavenge box should be hot, （）would occur.
A.seized piston B.defective atomizer C.scavenge fire D.too much LO
If exhaust temperatures are too high, you should check ...
单项选择题If exhaust temperatures are too high, you should check （）.
A.air cooler B.turbocharger C.charge air D.A+B+C
Defective timing gear in a diesel engine may lead to （）...
单项选择题Defective timing gear in a diesel engine may lead to （）.
A.smoky exhaust B.starting failure C.overload D.over speed
