The crankcase can not be opened（）the parts have been cooled down

The crankcase can not be opened ______ the parts have been cooled down.

A.if

B.as

C.unless

D.when

A.connecting rods

B.crankshaft

C.crankcase

D.through bolts

A.if

B.as

C.unless

D.when

A.cylinder casing

B.cylinder bore

C.crankcase door

D.aperture in the cylinder block

A.the cylinder cover

B.the bottom of bed-plate

C.the sump

D.the crankcase door

A.crankcase pressure

B.compression pressure

C.scavenge pressure

D.exhaust manifold pressure

Excessive oil foaming in the crankcase of a refrigeration compressor can result in _____.

A.overheated compressor bearings

B.excess lube oil viscosity

C.carbon deposits on the compressor piston rings

D.wax crystals forming in the lubricant

A.connecting rods

B.crankshaft

C.crankcase

D.through bolt

A.increase exhaust back pressure

B.causes excessive crankcase pressure

C.can only be detected by a compression check

D.decreases fuel consumption

A.crankcase

B.low lube oil temperature

C.excessive oil consumption

D.low bearing oil pressure