Sinclair SCV-750EB Service Manual page 103

Inspecting compressor oil
This oil is
black - it has
been
carbonized
Cloudy or
gray oil
indicates
abnormal
system
Effects of spoiled compressor oil
This oil is a little
yellow, but is clear
and transparent
and the condition
Worn crankshaft
Filter blocked by
impurities, which leads to
abnormal compressor
suction
Worn scroll plate
Worn scroll plate
Normal compressor
bearings
Seriously worn and
damaged bearings
is acceptable
This oil is still
transparent but there
are impurities which
may clog the filter
This oil contains
particles of copper
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