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单选题
（）diesel engines generally have two systems of lubrication:（）a total loss system feeding and a circulating system lubricating the running gear and cooling the pistons.
A
Large crosshead type；crossheads
B
High speed；the cylinders
C
Large crosshead type；the cylinders
D
Four-stroke；pistons and cylinders
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更多 “单选题（）diesel engines generally have two systems of lubrication:（）a total loss system feeding and a circulating system lubricating the running gear and cooling the pistons.A Large crosshead type；crossheadsB High speed；the cylindersC Large crosshead type；the cylindersD Four-stroke；pistons and cylinders” 相关考题
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单选题（）, so they are widely used on board ship nowadays.A
Diesel engines have more advantages in comparison with gasoline enginesB
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fuel combustionC
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单选题（） providing lubricating films, oil used in marine diesel engines have to remove heat from oil cooled piston.A
Except forB
BesideC
ExceptD
In addition to
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单选题（）uses one or two high pressure pumps for all the cylinders with one more standby, while（）have a separate high-pressure pump for each cylinder.A
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A marine diesel engine；most other enginesD
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cetane numberB
pour pointC
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quality of the oil
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单选题Cylinder lubrication oil for low speed main propulsion diesel engines is admitted to each cylinder during （）.A
the power strokeB
the compression strokeC
low load operation onlyD
periods of standby
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