Engine Oil System; Engine Oil Schematic - Cessna 150 STANDARD Service Manual

for swelling, cracking, or a pronounced set of the
part. Install with new parts all parts that show evi-
dence of wear or damage.
11-26. ENGINE OIL SYSTEM.
11-27. A wet-sump, pressure-lubricating oil sys-
tem is used in the 0-200-A series engines. Oil in
the sump passes through a sump pick-up tube,
through the suction screen in the tube, to the suction
side of the oil pump, From the pressure side of the
oil pump, oil is fed through the pressure oil screen,
or external full-flow oil filter, into the left oil gal-
lery. The oil flows forward through the left gallery,
across the crankcase, through the passages con-
nected by the camshaft front journal groove, and into
the right gallery, The oil pressure relief valve
I
LE
CODE
PRESSURE OIL
FROM GEAR TYPE
OIL PUMP
SUMP OIL, SUCTION
OIL, AND RETURN OIL
FROM RELIEF VALVE
OIL
TEMPERATURE OPTIONAL
~---GAGE
EXTERNAL
FILTER
OUTLET'
VALVE
FILTER------"
closes the rear end of the right gallery, The gal-
leries pressure-feed the main bearings, cam shaft
bearings, and hydraulic tappets. Connecting rod
bearings are lubricated from the main bearings
through drilled passages in the crankshaft, Valve
mechanisms are lubricated through hollow push-rods
from the tappets. Cylinder walls, piston pins, and
connecting rod bushings are spray-lubricated by oil
escaping from the connecting rod and main bearings,
Gears in the crankcase cover cavity are lubricated
by spray from the rear main and rear camshaft
bearings. Drilled passages from the crossover oil
gallery lubricates the vacuum pump adapter pad
mounted at the front lower side of the engine.
Throughout the engine, oil is returned to the sump by
gravity. The external full-flow oil filter is discussed
in paragraph 11-29.
OIL FILLER
CAP AND
DIPSTICK
~;--- PRESSURE
RELIEF
VALVE
Figure 11-3. Engine Oil Schematic
11-12 Change 3