1977 B Series Diagnostic Connector Wiring Diagram; Precautionary Service Measures; 1977 Pipe & Hose Connection Torque Chart - Pontiac TRANS AM 1977 Service Manual

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16-28 1977 PONTIAC SERVICE MANUAL
:ig. 18-2 1 1977 8 Series Diagnostic Connector Wiring
Diagram
ON-CAR SERVICE PROCEDURES
PRECAUTIONARY SERVICE MEASURES
Before any service is attempted which requies opening
of refrigerant lines or components, the person doing the work
should be thoroughly familiar with the information under
PRECAUTIONS IN HANDLING REFRIGERANT- 12,
PRECAUTIONS IN HANDLING REFRIGERANT
LINES AND FITTINGS, MAINTAINING CHEMICAL
STABILITY IN THE REFRIGERATION SYSTEM, AND
REFRIGERANT CHARGING PRECAUTIONS and
should follow very carefully the DISCHARGING,
ADDING OIL, EVACUATING AND CHARGING
PROCEDURES FOR C.C.O.T. A/C SYSTEMS
instructions given on the following pages for the unit being
serviced.
The major reasons behind these measures are safety and
the prevention of dirt and moisture in the system which can
restrict A/C system refrigerant flow.
The presence of moisture can also cause the formation
of hydocbloric or hydrofluoric acids in the system.
All sub-assemblies are dehydrated and sealed prior to
shipping. They are to remain sealed until just prior to making
connections. All sub-assemblies should be at room
temperature before uncapping (this prevents condensation of
moisture from the air that enters the system). If, for any
reason, caps are removed but the connections are not made,
parts should be resealed as soon as possible.
Sealing caps should be removed from sub-assemblies just
prior to making connections for final assembly. Use a small
amount of clean 525 viscosity refrigerant oil on all tube and
hose joints. Always use new O-rings dipped in the clean
refrigerant oil when assembling joints. The oil will aid in
assembly and help provide a leak-proof joint. When
tightening joints, use a second wrench to hold stationary part
of connection so that a solid feel can be attained. This will
indicate proper assembly.
I
1 I I
ALUMINUM OR
1
1
I
M ~ T ~ ~ ~ u B ~
I T HREAD AND^ 1
COPPER NOMINAL
: : ; : , " &
FITTING SIZE
TUBING
I
TORQUE
I
TORQUE TORQUE WRENCH SPAN
Fig.
18-22 1977
Pipe
&
Hose Connection Torque Chart
C A U T I 0 N
:
Tighten all tubing connections as
shown in torque chart (Fig. 18-22). Insuf7kient or
excessive torque when tightening can result in
loose joints or deformed joint parts. Either
condition can result in refngerant leakage.
All precautions should be taken to prevent damage to
fittings or connections. Any fittings getting grease or dirt on
them should be wiped clean with a cloth dampened with
trichlorethylene (naphtha, stoddard solvent or kerosene may
be used). Make sure fittings are dry prior to re-assembly. If
dirt, grease or moisture get inside pipes and cannot be
removed, the pipe should be replaced.