Adding Refrigerant Oil

It is important that only the specified type and quantity of refrigerant oil be used in the A/C compressor (19703) . If there is surplus oil in the system, too much oil will circulate with the refrigerant, reducing the cooling capacity of the system. Too little oil will result in poor lubrication of the A/C compressor .

During A/C Compressor Replacement

NOTE: The suction accumulator/drier (19C836) and A/C evaporator core orifice (19D990) must be replaced whenever the A/C compressor is replaced.

1. When reinstalling the existing A/C compressor or installing a new A/C compressor , remove as much oil as possible. On both A/C compressors , the shaft should be rotated about six to eight revolutions while pouring the oil from the ports. This effectively empties the A/C compressor of oil.

2. Obtain a clean container that can also be used as a measuring device.

3. Place the A/C clutch (2884) assembly on the A/C compressor shaft so the shaft can be rotated.

4. Rotate the shaft by hand six to eight revolutions, collecting the oil in a clean measuring device.

   NOTE: Service A/C compressors come pre-charged with 209 ml (7 oz) of oil.

5. If the amount of oil drained from the old A/C compressor is between 85-142 ml (3-5 oz), pour the same amount of clean Motorcraft YN-12 refrigerant oil into the new A/C compressor .

6. If the amount of oil that was removed from the old A/C compressor is greater than 142 ml (5 oz), pour 142 ml (5 oz) of clean Motorcraft YN-12 refrigerant oil into the new A/C compressor .

7. If the amount of refrigerant oil that was removed from the old A/C compressor is less than 85 ml (3 oz), pour 85 ml (3 oz) of clean Motorcraft YN-12 refrigerant oil into the new A/C compressor .

R-134a Refrigerant Oil

 CAUTION: Do not add R-134a refrigerant oil to an R-12 system. Also, do not add R-12 refrigerant oil YN-9 to an R-134a system. Mixing these two types of refrigerant oils may cause poor lubricant circulation resulting in component failure and damage to the A/C systems.

The refrigerant oil required for R-134a A/C systems is a polyalkalylene glycol (PAG) oil Ford part number F2AZ-19577-AB (Motorcraft YN-12a or YN-12) or equivalent meeting Ford specification WSH-M1C231-B. This type of refrigerant oil was made specifically for R-134a systems and is not suitable for use in R-12 systems. Never use an R-134a refrigerant oil in R-12 systems.

When it is necessary to replace a component of the refrigeration system, the correct procedures must be followed to ensure the total oil charge on the system is correct after the new component is installed. During normal A/C operation, some refrigerant oil is circulated through the system with the refrigerant and some is retained in the A/C compressor . If certain components of the system are removed for replacement, some of the refrigerant oil will go with the component. To maintain the original total oil charge, it is necessary to compensate for the oil lost by adding oil to the system with the replacement part.

Other Refrigerant System Components

Replacement of other refrigerant system components such as hoses, A/C compressor valves, and pressure switches does not require the addition of refrigerant oil.

Inspection and Assembly Requirements

NOTE: Any time a hose or component connection leak is observed, to correctly service the leak, the connector fitting must be separated, cleaned and a new O-ring installed. The O-ring and connector surfaces should be lubricated with clean refrigerant oil prior to assembly.

O-ring surfaces must be free of dirt, lint, burrs and scratches.

All o-rings must be lubricated with clean refrigerant oil YN-12 or equivalent immediately prior to installation.