Evacuation and Charging

Fig. 8 Refrigerant system service connections. Fixed orifice systems:

Charging From Small Containers
When charging from small cans, do not open manifold gauge set high pressure (discharge) gauge valve, as this can cause the containers to explode.
1. Connect a suitable refrigerant dispensing valve and valve retainer such as Motorcraft tool YT-280 or equivalent to the refrigerant can.
2. Connect manifold gauge set to system. Fig. 8. Connect hose normally connected to R-12 tank to special valve on small can adapter. Make sure valve is closed (full clockwise position).
3. When can is connected, charge system according to procedure under ``Charging from Drum.'' When can is empty, close valve and remove can. Connect new can open valve and continue charging until correct weight of refrigerant has entered system. Note capacity of refrigerant cans. When specifications require the use of a portion of a can, weigh it to ensure proper amount of refrigerant is installed.

Charging From Drum
1. With manifold gauges set valves closed to center hose, disconnect vacuum pump from manifold gauge set.
2. Connect center hose of manifold gauge set to refrigerant drum.
3. Purge air from center hose by loosening hose at manifold gauge set and open refrigerant drum valve. When refrigerant escapes from hose, tighten center hose connection at manifold gauge set.
4. On vehicles so equipped, disconnect wire harness connector at clutch cycling pressure switch. Install jumper wire across terminals of connector.
5. On all models, open manifold gauge set low side valve and allow refrigerant to enter system. Refrigerant can must be kept upright if vehicle low pressure service gauge port is not on suction accumulator/drier or suction accumulator fitting.
6. When system stops drawing refrigerant in, start engine and set control lever to A/C position and blower switch to ``HI'' position to draw remaining refrigerant into system.
7. When specified weight of refrigerant is in system, close gauge set low pressure valve and refrigerant supply valve.
8. On vehicles so equipped, remove jumper wire from clutch cycling pressure switch connector and connect connector to pressure switch.
9. On all models, operate system until pressures stabilize to check operation and system pressures. During high ambient temperatures, a high volume fan may be necessary to blow air through the radiator and condenser to cool engine and prevent excessive refrigerant system pressures.
10. When charging is complete and system operating pressures are normal, disconnect manifold gauge set from vehicle and install protective caps on service gauge port valves.