GM Service Manual Online
For 1990-2009 cars only

Adding Oil

The Harrison HT-6 compressor system in all C/K models requires polyalkaline glycol (PAG) refrigerant oil in the quantities listed below:

    • Without Aux. A/C -- 240 ml (8 fl oz)
    • With Aux. A/C -- 330 ml (11 fl oz)

New oil quantities must be added to the system during component replacement. With no signs of excessive leakage, add oil to the components as follows:

    • All Compressors (drain and measure the oil)
       - If less than 30 ml (1 fl oz) is drained, add 60 ml (2 fl oz) to the new compressor.
       - If more than 30 ml (1 fl oz) is drained, add the same amount that was drained to the new compressor.
    • Accumulator -- Add 105 ml (3.5 fl oz) of new oil to the replacement accumulator in order to compensate for the oil retained by the original accumulator desiccant and bag assemblies. Only replace the accumulator if the leaking is due to a perforation, a damaged O-ring seal seat, or damaged threads.
    • Evaporator -- Add 90 ml (3 fl oz) of new refrigerant oil.
    • Condenser -- Add 30 ml (1 fl oz) of new refrigerant oil.

Refrigerant Oil Loss Due to a Large Leak

If a large refrigerant leak causes the abrupt loss of refrigerant charge, approximately 90 ml (3 fl oz) of refrigerant oil will be carried out of the system suspended in the refrigerant. Any failure that causes an abrupt refrigerant discharge will experience this oil loss. Failures that allow the refrigerant to seep or bleed off over time do not experience the same degree of oil loss.

Upon the replacement of a component that caused a large refrigerant leak, add 90 ml (3 fl oz) of new polyalkaline glycol (PAG) refrigerant oil plus the desired amount of oil for the particular component. Refer to Adding Oil.