Pontiac Fiero 1988 Service Manual page 327

6A2-2 2.8 LITER V-6 ENGINE P CARLINE
EXHAUST MANIFOLDS
The exhaust manifolds are cast nodular iron.
ENGINE LUBRICATION
(Figuies 1 thru 4)
Fall pressure lubrication, through a full flow oil
filter, is furnished by a gear type oil pump. Oil is drawn
up through the pick up screen and tube and passed
through the pump to the oil filter.
The oil filter is a full flow paper element unit. An
oil filter by-pass is used to ensure adequate oil supply,
should the filter become plugged or develop excessive
pressure drop. The by-pass is designed to open at 69-83
kPa.
Oil is routed from the filter to the main oil gallery,
rifle drilled above the camshaft to the left of the
camshaft centerline. This gallery supplies the left bank
hydraulic lifters with oil.
Oil is directed from the left gallery, by means of
intersecting passages, to the camshaft bearings and
right oil gallery.
The hydraulic lifters pump oil up through the
push rods to the rocker arms. Oil draining back from
the rocker arms is directed, by cast dams in the
crankcase casting, to supply the camshaft lobes. Oil
also drains past specific hydraulic lifter flats to oil
camshaft lobes directly.
The passages supplying oil to the camshaft
bearings also supply the crankshaft main bearings
through intersecting vertically drilled holes. Oil from
the crankshaft main bearings is supplied to the
connecting rod bearings by means of intersecting
passages drilled in the crankshaft.
The front cam bearing has a .25 mm deep slot on
its outside diameter to supply oil to the cam sprocket
thrust face.