A.increase back pressure during the exhaust process
B.facilitate periodic replacement of the valves
C.reduce the pumping loss associated with scavenging
D.reduce tension on valve springs
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A.excessive ring action
B.excessive ring temperature
C.improper ring rotation
D.excessive ring face wear
A.higher speed required
B.flywheel-effect
C.lower starting temperatures
D.higher compression pressures
A.most critical in a four-stroke cycle diesel engine
B.most critical in a two-stroke/cycle diesel engine
C.most critical in a four-stroke/cycle diesel engine if it is turbocharged
D.of equal importance in a two-stroke/cycle diesel engine as in a four-stroke/cycle diesel engine
A.The oil control rings will seal improperly and wear rapidly
B.The piston will overheat due to insufficient lubrication
C.Excessive oil will remain on the cylinder wall
D.Light brown smoke will emanate from the engine exhaust
A.keep piston crown temperatures elevated for smoother combustion
B.reduce the possibility of overheating the top compression ring
C.help retain the heat of compression to prevent ignition delay
D.help retain the heat of compression to prevent combustion knock
A.dispersant additives
B.floc point
C.alkalinity additives
D.ignition quality
A.starting the engine hot
B.knurling the piston skirt
C.operating an overheated engine
D.using scuff resistant piston rings
A.the amount of lube oil additives increase
B.piston speeds increase
C.injection pressure decrease
D.engine speeds decrease
A.less piston slap and quieter running
B.increased crankshaft bearing wear
C.slightly greater piston wear
D.decreased side pressures
A.Liner wear is distributed equally between the upper and lower portions of the cylinder
B.Excessive liner wear causes wear between piston ring and groove
C.Excessive, but uniform liner wear will not cause wear between piston ring and groove
D.Liner wear is normally greatest in the middle of the cylinder
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