Pontiac FIREBIRD 1972 Service Manual page 565

V-8 ENGINE 6-53
EXHAUST SYSTEM
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pass through a cross-over pipe which passes beneath the
engine to the right side. At this point the exhaust pipe
Two cast iron exhaust manifolds are used, one for each
from the right manifold joins the cross-over pipe and gases
bank of cylinders. Exhaust gases from the left manifold
are carried rearward to the mumer and tailpipe.
THE FOLLOWING INFORMATION ON ENGINE SERVICE
SHOULD BE NOTED CAREFULLY, AS IT IS IMPORTANT IN
PREVENTING DAMAGE AND CONTRIBUTING TO RELIA-
BLE ENGINE PERFORMANCE.
Cleanliness is a primary factor when servicing the V-8
engine. The slightest particle of dirt that finds its way into
a hydraulic lifter may cause a malfunction.
Since any dirt which may enter the oil galleries or passages
in the engine could eventually get to a lifter, cleanliness
should be exercised when any part of the engine is
removed or disassembled. When a cylinder head is
removed for any purpose, it is necessary to remove the
intake manifold and/or push rod cover. This exposes the
lifters to any dirt which may fall from the upper portion
of the block or which may be carried in the air. Thus it
is wise to cover the lifter galleries until ready to reassemble
the engine.
When lifters are removed for any reason, they should
immediately be placed in a valve lifter storage box in the
order in which they were removed. It is important for two
reasons. First, it is the easiest way to keep lifters clean.
Second, lifters should always be replaced in the same
bosses from which they were removed.
Valves, valve lifters, push rods, rocker arms, rocker arm
balls, and rocker arm ball nuts should always be kept in
sets and returned to their original positions. These parts
will tend to mate as the engine operates and will provide
more satisfactory operation when kept together. By stor-
ing lifters in a storage box and valves, push rods, rocker
arms, balls and nuts in a holding stand whenever they are
removed, they can easily be kept in sets for identification
during assembly. In addition to keeping the parts in sets,
the push rods should be replaced with the same end up.
In other words, replace push rods so that the same end
contacts the rocker arm as before the engine was disassem-
bled. Push rods will be polished somewhat in the area
where the rod passes through the head.
GENERAL INFORMATION ON ENGINE SERVICE
PERIODIC SERVICE
When hydraulic valve lifters are disassembled, the various
parts of each lifter must be kept together. This is especially
important since the lifter body and plunger are selectively
fitted. The use of the special tray included with cleaning
tank J 5821 will aid in keeping the parts of each lifter
together when lifters are being serviced.
Cylinder head bolts should be installed without thread
sealer of any kind.
,
When raising or supporting the engine for any reason, do
not use a jack under the oil pan or crankshaft pulley. Due
to the small clearance between the oil pan and the oil
pump, jacking against the oil pan may cause it to be bent
against the pump. The result would be a telegraphed noise
which would be difficult to trace. The crankshaft pulley
is sheet steel and will not support engine weight. Always
use engine lifting tool J 235 15.
It should be kept in mind, while working on the engine,
that the twelve-volt electrical system is capable of violent
and damaging short circuits. When performing any work
where electrical terminals could possibly be grounded, the
ground cable of the battery should be disconnected at the
battery.
Never reverse battery leads, even for an instant, as reverse
polarity current flow will damage diodes in the generator.
Any time the carburetor or air cleaner is removed, the
intake opening should be covered. This will protect
against accidental entrance of foreign material which
could follow the intake passage to the cylinder and cause
extensive damage when the engine is started.
In the mechanical procedures described in this section,
generally no references will be made to the removal of
optional equipment such as power steering pump, air con-
ditioning compressor, etc. Should it become necessary to
remove any such item to perform other service refer to the
appropriate section of the manual for specific information.
There are no periodic services required on the mechanical filter, etc. Procedures and recommendations for these ser-
portions of the engine. Periodic services connected with vices will be found in appropriate sections of this manual,
the engine consist of tune-up, lubrication, replacing oil and the Owner's Manual.