Cessna 150 Series Service Manual page 137

11-30. ENGINE OIL SYSTEM. (Refer to figure 11-3.) pressure relief valve closes the rear end of the right
gallery.
The galleries pressure-feed the main bear-
11-31. DESCRIPTION. A wet-sump, pressure-
ings,- cam shaft bearings, and hydraulic tappets.
lubricating oil system is used in the 0-200-A series
Connecting rod bearings are lubricated from the main
engines. Oil in the sump passes through a sump pick-
bearings through drilled passages in the crankshaft.
up tube, through the suction screen in the tube, to the
Valve mechanisms are lubricated through hollow push-
suction side of the oil pump.
From the pressure side rods from the tappets. Cylinder walls, piston pins,
of the oil pump, oil is fed through the pressure oil and connecting rod bushings are spray-lubricated by
screen, or the external full-flow oil filter, into the oil escaping from the connecting rod and main bear-
left oil gallery.
If the optional oil cooler is installed, ings. Gears in the crankcase cover cavity are lubri-
the oil passes the oil cooler bypass valve, then to the
cated by spray from the rear main and rear camshaft
cooler via a flexible hose connection outside the crank-
bearings. Drilled passages from the crossover oil
case, thru the cooler and back to the engine via a gallery lubricates the vacuum pump adapter pad
second flexible hose connection. The oil flows for- mounted at the front lower side of the engine.
ward through the left gallery, across the crankcase, Throughout the engine, oil is returned to the sump to
through the passages connected by the camshaft front
the sump by gravity.
journal groove, and into the right gallery.
The oil
OIL FILLER
CAP AND
OIL COOLER
BYPASS VALVE
SUMP
OPTIONAL
O|FILTER
EXTERNAL
BYPASS
PRESSURE
OIL PUMP
FILTER
FigOUTLET
OIL
PRESSURE OIL
TEMPERATURE FROM GEAR TYPE
TEMPERATURE OPTIONAL
OIL PUMP
EXTERNAL
FILTER
SUMP OIL, SUCTION
OIL, AND RETURN OIL
FROM RELIEF VALVE
Figure 11-3. Engine Oil Schematic
11-12