2016 C300 - 205.048, with 274.9 motor; equipped with R134a.

Have to renew refrigerant compressor on this vehicle due to failure of compressor's integral refrigerant metering valve.

New dealer supplied compressor is labeled 000 830 30 02 80; label states ND-oil 12; 80 cm3.

In preparation for compressor renewal, the system's refrigerant was evacuated; no oil was extracted.

WIS article AR83.30-P-1760LW (Drain, Evacuate and Recharge) details the following lubricant refill quantities specific to this vehicle:

a) Compressor oil extracted during evacuation - 0 cm3 [none was extracted]

b) add new oil to the refrigerant circuit according to the oil filling capacity noted during extraction - 0 cm3 [again, none extracted]

c) additional oil filling quantity after replacement of refrigerant compressor - 20 cm3 (per BF83.55-P-1007-01J)

d) additional oil filling quantity after replacement of desiccant cartridge - 20 cm3 (per BF83.55-P-1009-91J)


As such, according to these quidelines, installation of a new compressor and desiccant bag in a system with no history of refrigerant loss or other faults/component renewals and no evacuation of lubricant during removal of refrigerant from the system should have 40 cm3 of ND-oil 12 added prior to recharging.

The new compressor was bench mounted, inverted, clutch rotated and found to contain less than 5 cm3 of lubricant.

Question is... to what does the 80 cm3 on the new compressor's external label refer? The unit was purchased new from Mercedes, was not pressurized and contained no lubricant volume of consequence on board.

Does 80 cm3 represent the system's total refrigerant oil capacity?