Hudson 1955 Rambler, Техническое и сервисное руководство

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ALL SEASON AIR CONDITIONING SYSTEM 21
The compressor lubricant is soluble in Freon-
12. To prevent pulling too much oil out of the
system, release the charge slowly so that the
oil remains as the Freon vaporizes into
atmosphere.
If there is no oil foaming out with the
Freon, the valve may be opened wider to allow
the gas to escape more rapidly. It would be
advisable to release the charge in an open
area other than the one wherein subsequent
service operations such as checking for leaks
would take place. This would prevent contami-
nating the area with Freon gas and cause
erroneous and false leak detection.
The same operation may be performed on the
suction service valve to assure complete
release of the charge in the system.
This procedure should be followed in service
operations where components are removed.
EVACUATING THE SYSTEM
The system should be evacuated every time it
has been opened for a service operation such
as a replacement of a part or line. Air and
moisture may have entered the system when it
was opened. It is advisable to evacuate the
system every time a part has been removed from
the system or whenever a charge has been lost
through a leak or loose connection. The system
should be evacuated prior to charging if it
has been standing for a period of time without
a charge. In discussing service operations
requiring evacuation, only reference to evac-
uation will be made. The following procedure
should be followed every time evacuation is
necessary.
The compressor is used to evacuate the system.
The following procedure must be followed
very carefully to prevent any damage to the
compressor and its parts. Make certain the
system is completely discharged. No Freon gas
should be present during this operation.
Remove the protective caps from both service
valve stems.
Install Gauge Line, Tool J-5418, from
suction service valve port to compound gauge
fitting on the gauge manifold set ( Fig. 25).
Install the gauge line from discharge
service valve port fitting to the high
pressure gauge fitting on the gauge manifold
set.
Install gauge line to the center connection
on the gauge manifold set.
The hand valve on the compound gauge is
closed to the center connection of the gauge
manifold set. The compound gauge will still
register low side pressure. The hand valve on
the pressure gauge is open to the center
connection.
The suction service valve is moved to the
"cracked" position by turning the valve stem
in two to three turns. The discharge service
valve is "closed" by turning the valve stem
in all the way. The discharge service valve
gauge port is open to the atmosphere through
1. Gauge Line, Compound Gauge to Suction Service Valve
2. Gauge Line, to Atmosphere or Freon Drum for Charging
3. Gauge Manifold Set
4. Gauge Line, Discharge Service Valve to Pressure Gauge
FIGURE 25— Installation of Gauge Set,
Tool J-5725
the open hand valve on the gauge manifold
set and the open gauge line (Fig. 26) .
The gauges both should register "0" at this
time as there is no pressure present in the
system.
The discharge service valve being closed
and with the gauge port open, air pumped out
by the compressor is exhausted through the
open gauge line attached to the center
connection. With the discharge service valve
closed, the system is closed off so that as
the compressor pumps, the system is evacu-
ated back to the closed valve.
Check the oil level in the compressor.
Start the engine and operate the compres-
sor for a second or two at a time for three
or four times to slowly reduce the internal
pressure. Then run continuously observing
the compound gauge. If the compressor is
efficient, it should pump down from 12" to
18" vacuum quickly.
IMPORTANT: DO NOT RUN MORE THAN 10 TO
15 MINUTES AS IT IS POSSIBLE TO
DAMAGE THE COMPRESSOR.
If a 12" to 18" vacuum cannot be reached,
the compressor is evidently defective or a
leak is present in the system.