Dodge RAM 1500 1998 Owner's Manual page 2532

DR
PLUMBING (Continued)
STANDARD PROCEDURE
STANDARD PROCEDURE - HANDLING TUBING
AND FITTINGS
CAUTION: The system must be completely empty
before opening any fitting or connection in the
refrigeration system. Open fittings with caution
even after the system has been emptied. If any
pressure is noticed as a fitting is loosened,
retighten fitting and evacuate the system again.
A good rule for the flexible hose lines is to keep the
radius of all bends at least 10 times the diameter of
the hose. Sharper bends will reduce the flow of
refrigerant. The flexible hose lines should be routed
so they are at least 3 inches (80 mm) from the
exhaust manifold. Inspect all flexible hose lines to
make sure they are in good condition and properly
routed.
The use of correct wrenches when making connec-
tions is very important. Improper wrenches or
improper use of wrenches can damage the fittings.
The internal parts of the A/C system will remain sta-
ble as long as moisture-free refrigerant and refrig-
erant oil is used. Abnormal amounts of dirt,
moisture or air can upset the chemical stability.
This may cause operational troubles or even seri-
ous damage if present in more than very small
quantities. Before disconnecting a component,
clean the outside of the fittings thoroughly to pre-
vent contamination from entering the refrigerant
system.
When opening a refrigeration system, have every-
thing you will need to repair the system ready. This
will minimize the amount of time the system must
be opened. Cap or plug all lines and fittings as
soon as they are opened. This will help prevent the
entrance of dirt and moisture. All new lines and
components should be capped or sealed until they
are ready to be used. Before connecting a compo-
nent, clean the outside of the fittings thoroughly to
prevent contamination from entering the refrigerant
system.
All tools, including the refrigerant dispensing mani-
fold, the manifold gauge set, and test hoses should
be kept clean and dry.
Kinks in the refrigerant tubing or sharp bends in
the refrigerant hose lines will greatly reduce the
capacity of the entire system. High pressures are pro-
duced in the system when it is operating. Extreme
care must be exercised to make sure that all connec-
tions are pressure tight. Dirt and moisture can enter
the system when it is opened for repair or replace-
ment of lines or components. The refrigerant oil will
absorb moisture readily out of the air. This moisture
will convert into acids within a closed system.
STANDARD PROCEDURE - DIODE
REPLACEMENT
(1) Disconnect and isolate the battery negative
cable. If the vehicle has dual batteries, remove the
negative cable from both batteries.
(2) Locate the diode in the harness, and remove
the protective covering.
(3) Remove the diode from the harness. Note the
direction of current flow (Fig. 1).
Fig. 1 Diode Identification
1 - CURRENT FLOW
2 - BAND INDICATES CURRENT FLOW
3 - DIODE AS SHOWN IN WIRING DIAGRAMS
(4) Remove the insulation from the wires in the
harness. Only remove enough insulation to solder in
the new diode.
(5) Install the new diode in the harness, making
sure current flow is correct. If necessary refer to the
appropriate wiring diagram for current flow.
(6) Solder the connections together using rosin
core type solder only. Do not use acid core solder.
(7) Tape the diode to the harness using electrical
tape. Make sure the diode is completely sealed from
the elements.
(8) Reconnect the battery negative cable(s) and
test the affected systems.
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