shaft end play. A sintered iron (TBI engine and steel
billet Turbo III engines) timing belt sprocket is
mounted on the cam nose, and a hydrodynamic oil
seal is used for oil control at the front of the cam-
shaft.
ACCESSORY SHAFT: The iron accessory shaft
has two bearing journals and is housed in the for-
ward facing side of the block. A hydrodynamic seal,
installed in an aluminum housing attached to the
block, provides retention, shaft thrust, and oil con-
trol. The accessory shaft is driven by the timing belt
through a sintered iron (TBI engine and steel billet
Turbo III engines) sprocket mounted on the nose of
the accessory shaft. The accessory shaft in turn
drives the oil pump and distributor on 2.2/2.5L and
2.5L FFV and the oil pump only on Turbo III.
VALVES: The valves are actuated by roller cam
followers which pivot on stationary hydraulic lash
adjusters. The valve train with 40.6 mm (1.60 inch)
diameter intake valves and 35.4 mm (1.39 inch) di-
ameter exhaust valves employ viton rubber valve
stem seals except 2.5L FFv . the 2.5L FFV valve
stem seals are made of special rubber compound
which resist the deteriorating effects of methanol
fuel by-products that enter the oil during combus-
tion. Valve springs, spring retainers, and locks are
conventional. For Turbo III engines the valves are
actuated by roller tipped rocker arms with hydraulic
lash adjusters which pivot on a shaft. The valve train
with 33.88 mm (1.33 in.) diameter intake valves are
arranged in line opposite of the 29.26 mm (1.15 in.)
diameter exhaust valves employ locking valve stem
seals. Valve springs, spring retainers, and locks are
not interchangeable with other engines.
BALANCE SHAFTS: 2.2 Turbo III and 2.5L en-
gines are equipped with two counter rotating balance
shafts installed in a carrier attached to the lower
crankcase.
The
shafts
are
interconnect
through
gears. These gears are driven by a short chain from
the crankshaft, to rotate at two times crankshaft
speed. This counterbalances certain engine recipro-
cating forces.
INTAKE MANIFOLDS: All intake manifolds are
aluminum castings, attached to the cylinder head
with eight bolts. N.A. engines use a four branch de-
sign. This long branch fan design enhances low and
midspeed torque. It also features an integrally cast
water crossover passage to warm incoming fuel/air
mixture, plus an EGR mounting boss and PCV inlet.
The Turbo III engine intake manifold is a log type
with tuned runners. The manifold is machined to ac-
cept fuel injectors near the ports of each cylinder.
EXHAUST MANIFOLDS: The exhaust manifolds
are made of nodular cast iron for strength and high
temperatures. All naturally aspirated (N.A.) and tur-
bocharged engines exit exhaust gasses through a ma-
chined, articulated joint connection to the exhaust
pipe. 2.2/2.5L and 2.5L FFV manifolds intermesh
with the intake manifold at the cylinder head.
N.A. engines use a four branch design with cylin-
ders one and four joined and cylinder two and three
joined to exit at the outlet.
The Turbo III engine exhaust manifold also carries
the turbocharger. This manifold has a modified log
type collector with exhaust gasses directed to and
through the turbocharger to exit the conical (articu-
lated joint) outlet machined into the turbocharger ex-
haust elbow.
ENGINE LUBRICATION: Refer to Group 0 Lu-
brication and Maintenance for recommended oil to be
used in various engine application. System is full
flow filtration, pressure feed type. The oil pump is
mounted within the crankcase and driven by the ac-
cessory shaft. Pressurized oil is then routed through
the main oil gallery, running the length of the cylin-
der block, supplying main and rod bearings with fur-
ther routing (for 2.2L turbo III and 2.5L engines) to
the lower balance shaft assemblies. Pistons are lubri-
cated from directed holes in the connecting rod as-
semblies.
Camshaft
and
valve
mechanisms
are
lubricated from a full-length cylinder head oil gallery
supplied from the crankcase main oil gallery.
9 - 10
2.2/2.5L ENGINE
Ä