During Component Replacement

Refrigerant Oil Addition
When replacing components of the air conditioning refrigerant system, measured quantities of Motorcraft Refrigerant Oil YN-12b or equivalent meeting Ford specification WSH-M1C231-B which is required in systems using R134a refrigerant must be added to the replacement components. It is important that only the specified type and quantity of refrigerant oil be used. A surplus of oil will reduce the cooling capacity of the system. Too little oil will result in poor lubrication of the A/C compressor.

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.

During A/C Compressor Replacement
When replacing the A/C compressor, measured quantities of Motorcraft Refrigerant Oil YN-12b or equivalent meeting Ford specification WSH-M1C231-B should be added to the A/C compressor. It is important that only the specified Panasonic compressor type and quantity of refrigerant oil be used. A surplus of oil will reduce the cooling capacity of the system. Too little oil will result in poor lubrication of the A/C compressor.

When the A/C compressor operates, oil gradually leaves the A/C compressor and circulates through the system with the refrigerant. Eventually a balanced condition is reached in which a certain amount of oil is retained in the A/C compressor and a certain amount is continually circulated. If the A/C compressor is removed after the system has been operated, some oil will go with it. To maintain the original oil charge, it is necessary to compensate for the amount of oil lost with the old A/C compressor by adding an equal amount to the new A/C compressor. Motorcraft Refrigerant Oil YN-12b or equivalent meeting Ford specification WSH-M1C231-B should be added to the replacement components as follows:

A new service replacement A/C compressor contains 200ml (6.78 fluid ounces) of the specified refrigerant oil. Prior to installing the replacement A/C compressor, drain the oil into a clean calibrated container. Then drain the oil from the old A/C compressor into another clean calibrated container. Add the same amount of clean refrigerant oil as removed from the old A/C compressor to the new A/C compressor, plus 20ml (0.6762 fluid ounces).


During Component Replacement
If a refrigerant system component is removed after the system has been operated, some oil will go with it. To maintain the original oil charge, it is necessary to compensate for the amount of oil lost with the old component by adding an equal amount to the new component. Clean refrigerant oil should be added to the replacement components as follows:
- A/C evaporator core - Add 90ml (3 fluid ounces).
- A/C condenser core - Add 30ml (1 fluid ounce).
- Suction accumulator/drier - Add 30ml (1 fluid ounces).
- A/C refrigerant line - 30ml (1 fluid ounce).

Pour clean Motorcraft Refrigerant Oil YN-12b or equivalent meeting Ford specification WSH-M1C231-B directly into the replacement component. If any other components, such as the A/C evaporator core orifice is replaced then no additional refrigerant oil is necessary.

When servicing A/C systems for concerns that do not require major component replacement, add 2 oz. of Motorcraft Refrigerant Oil YN-12b or equivalent meeting Ford specification WSH-M1C231-B to the system before recharging. Repairs considered minor, for example, are O-ring leaks, charge port leaks, compressor shaft seal leaks, and hose leaks.



Other Refrigerant System Components
If any other components need replacement, add 2 oz. of Motorcraft Refrigerant Oil YN-12b or equivalent meeting Ford specification WSH-M1C231-B to the system before recharging. Repairs considered minor are O-ring leaks, charge port leaks, compressor shaft seal leaks, hose leaks, etc.