Pontiac FIREBIRD 1972 Service Manual page 639

ENGINE COOLING AND LUBRICATION 6A- 19
Fig. 6A-22 Engine Lubrication (V-8 except 307)
piston pins. Timing chain and sprockets receive metered
jet lubrication, as do the fuel pump eccentric and rocker
arms. A hole in the block from the valve lifter gallery
through the distributor boss lubricates the distributor
shaft and bushings.
Oil flow through the engine is as follows:
V-8 EXCEPT 307
Oil is first supplied by the pump and filter to two parallel
oil galleries drilled in the block on each side of the cam-
shaft. Oil travels from rear to front in the left gallery and
from front to rear in the right gallery. The rear crankshaft
and camshaft bearings receive oil from a hole drilled
through the passage connecting the filter to the left gal-
lery. All other crankshaft bearings receive oil from holes
drilled into the left gallery. The remaining four camshaft
bearings are supplied by a hole drilled vertically from each
crankshaft bearing journal to the camshaft bearing journal
above.
Hydraulic valve lifters are fed by holes drilled from each
lifter boss to the oil galleries (Fig. 6A-22). Oil from each
lifter is directed up through hollow push rods to the rocker
arms. Oil then passes through a hole in the push rod
contact area of the rocker arm and fills it. This supply
lubricates the rocker arm ball. Overflow lubricates the top
of the valve stem and other valve train surfaces.
Lubrication of the camshaft thrust plate, timing chain and
sprockets, fuel pump eccentric and fuel pump rocker arm
is provided for by a passage in the front of the camshaft.
A lateral hole in the front bearing journal indexes with the
camshaft bearing oil supply hole in the block once each
revolution. An oil jet then squirts out of the horizontal
hole in the end
o f
the camshaft toward the front of the
engine. Part of this oil is projected straight forward,
against the camshaft thrust plate. Another part of the oil
is projected downward through the grooves in the block
and thrust plate to the crankshaft timing chain sprocket.
Oil passing down the groove also is forced out the hole in
the thrust plate. The jet of oil from this hole is timed to
pass through one of the openings in the camshaft sprocket
and strike the fuel pump eccentric and rocker arm.
The oil pan has been made as deep as possible to provide
the maximum depth of oil. This minimizes splashing and
foaming which would be detrimental to the operation of
hydraulic lifters. It also insures a constant supply of oil
during rapid acceleration and sharp turns. Additional pro-
tection against splashing and foaming is provided by the
oil pan baffle. The'baffle extends across the entire area of
the oil pan, preventing oil which is thrown off the crank-
shaft from churning that in the sump.
307 V-8
Refer to Figure 6A-23 for oil circulation on 307 V-8.