- Compressor: Remove and drain the oil. Measure the oil removed. Drain the oil from the new compressor. If more than 30 ml is drained from the compressor being replaced, add that amount of new oil to the new compressor. If less than 30ml is drained from the old compressor, add 60ml of clean oil to the new compressor.- Evaporator: Add 90ml (3 fl oz). Compressor: Remove and drain the oil. Measure the oil removed. Drain the oil from the new compressor. If more than 30 ml is drained from the compressor being replaced, add that amount of new oil to the new compressor. If less than 30ml is drained from the old compressor, add 60ml of clean oil to the new compressor.