Hudson 1955 Rambler, Technical & Service Manual

Page: 277 / 292

ALL SEASON AIR CONDITIONING SYSTEM 27
process must be repeated. When bleeding off
the excessive amount of refrigerant, a cloth
placed over the gauge line opening will
prevent the refrigerant or any oil from
contacting on the car or persons.
LEAK TEST PROCEDURE
Outward leaks of Freon-12 are detected and
located with the help of a device called a
Halide Torch, Tool J-6048. It is a torch to
which has been added an "Exploring Tube"
through which air is drawn by injector
action from points at which leakage is
suspected. The torch uses Propane gas. The
cylinder is not refillable. Obtain cylinder
from supplier. When cylinder is exhausted,
discard in safe place. Do not throw in
incinerator or other fire. When torch is not
in use, do not store near fire, or in room
used for habitation.
A copper reaction ring, heated red hot by
the flame, is located where the air is drawn
into the flame. If the slightest trace of
Freon comes through the exploring tube, the
normally blue flame changes to green, thus
indicating the free end of the exploring
tube is being held near a point of leakage
(Fig. 29).
Operation of Halide Leak Detector
To operate the Halide Leak Detector, open
valve and light.
When the copper reaction ring becomes hot,
adjust the valve to produce a flame
3
/
8
"
above reaction ring. The smaller the flame,
the more sensitive the burner is to leaks.
Action of the torch may be checked by holding
the end of the exploring tube where there is
known to be Freon gas and noting whether the
flame turns green. A flame that is yellow or
white indicates that the exploring tube is
clogged.
Hold the free end of the exploring tube close
to every joint and pass it slowly all around
the joint. It takes some time for any
escaping refrigerant gas to be drawn through
the exploring tube into the torch flame, so
this part of the work must not be hurried.
The worse the leak, the greater the concen-
tration of refrigerant carried into the
torch, the darker will be the green of the
torch flame. Large leaks may turn the flame
to a bright purple or may extinguish it by
keeping air and oxygen from the flame.
CAUTION: Avoid breathing the poison-
ous fumes and black smoke produced
from the burner of the torch if Freon
gas is added to flame.
With very large leaks, the surrounding air
may be saturated with so much Freon that the
torch flame remains green all the time. This
could happen where there is poor ventilation.
Several commercial type leak detection
solutions are available that may also be
used.
FIGURE 29— Testing for Freon Leaks with
Halide Leak Detector, Tool 1-6048
If a leak is detected by either method, do
not run the system as the entire charge may
be lost. Dirt and moisture may be drawn into
the system.
If the system has lost its charge, it must
be completely leak tested, leaks repaired,
recharged, and checked again to make sure
that there are no other leaks in the system.
If a leak is detected at a flare connec-
tion, retighten with suitable wrenches. Care
must be exercised in tightening flared
connections; copper is soft and the flare
can be damaged.
If, after tightening, the leak is still
apparent, the system must be discharged, the
damaged connection or line replaced, and
system recharged.
New gaskets may be required, packings in
service valves, or whatever other corrective
measures are required for the part at fault.
Threaded joints may be made tight by
applying a paste made from litharge, also
called yellow lead, or lead monoxide, and
glycerine mixed to the consistency of library