Oil from the oil pan is pulled through the suction bell for
the oil pump (10) by oil pump (8). The oil is sent by the
pump to an oil passage in the front cover for the engine
(3). Oil from this passage goes to the cylinder block and
on to base for the oil cooler (5). The base for the oil
cooler is on the left side of the engine, near the front of
the engine. Bypass valve (11), in the base for the oil
cooler, will let the oil go around the oil cooler (7) when
the oil is cold or if the restriction in the oil cooler is more
than the other parts of the system. A difference in
pressure of 12 to 15 psi (85 to 105 kPa) between the oil
inlet and the oil outlet will open the bypass valve.
Oil from the oil cooler goes to the oil filters. Bypass
valve (12), in the base for the oil cooler will let oil go
around oil filters (13) if there is a restriction in the oil
There are two pressure outlets in the base for the oil
cooler. The pressure outlets are on the outlet side of the
oil cooler and oil filters. The pressure outlets are for the
sending unit and switch for the oil pressure.
Oil from the oil filters (13) goes through a passage in the
cylinder block to oil manifold (4). The oil manifold is in
the center of the cylinder block, above the camshaft,
and goes the full length of the cylinder block. Oil goes
from the oil manifold to the bearings for the camshaft.
There are grooves in the bores in the cylinder block
around the bearings for the camshaft. The bearing
surfaces (journals) on the camshaft get lubrication from
these grooves through a hole in the bearings for the
Some of the oil goes around the grooves and down
through a passage to a hole and groove in the top half
of the main bearing. Oil from the hole and groove gives
lubrication to the bearing surfaces (journals) of the
crankshaft for the main bearings.
Oil gets into the crankshaft through holes in the bearing
surfaces (journals) for the main bearings. Passages
connect the bearing surface (journal) for the main
bearing with the bearing surface (journal) for the
connecting rod. The piston pins get lubrication from oil
thrown by other parts.
Oil for the rocker arms comes from the oil manifold (4)
through passages in the cylinder block. The passages in
the cylinder block are in alignment with a passage in
each cylinder head. The passage to the cylinder head
on the left side is near the front of the cylinder block.
The passage to the cylinder head on the right side is
near the rear of the cylinder block.
The passage in each cylinder head sends the oil into an
oil hole in the bottom of the mounting surface of the
bracket that holds the shaft for the rocker arms. The oil
hole is in the front bracket on the left side and in the rear
bracket on the right side. The oil then goes up through
the bracket and into the center of the shaft for the rocker
arms. Oil goes along the center of the shaft to the
bearings for the rocker arms. From the rocker arms, the
oil is pushed through small holes to give lubrication to
the valves, push rods, cam followers, and camshaft
After the lubrication oil has done its work, it will return to
the oil pan for the engine.
SCHEMATIC OF OIL PASSAGES