PeachParts Mercedes-Benz Forum - View Single Post - Refrigerant / Oil Capacity on W108 with A6

Tomguy · #6 06-14-2019, 11:59 AM

If the new compressor came with no oil in it, I would suggest 4-6oz. This is if your system has NOT been flushed. There will be oil still in the old condenser and evaporator. You don't want to overfill with oil. You're replacing the dryer so maybe closer to the 6oz. YMMV and I would suggest looking for a specific A6 compressor spec sheet. Here's an R134a system in a car I have with the FSM fill guides.
While this is for a Chrysler LH platform the guide is pretty much universal for R134a systems with a roughly 25oz R134a capacity:

COMPONENT NAME ml. oz.
Total Air Conditioning System 150 ml. 5.00 oz.
Condenser 30 ml. 1.00 oz.
Evaporator 59 ml. 2.00 oz.
Filter/Drier 30 ml. 1.00 oz.
Line Blown 44 ml. 1.50 oz.

VERIFY REFRIGERANT ND8 LUBRICANT LEVEL
(1) Discharge refrigerant system using a recycling/
reclaiming equipment if a charge is present.
(2) Disconnect refrigerant lines from A/C compres-
sor. Cap the open lines to prevent moisture from
entering system.
(3) Remove compressor from vehicle.
(4) From suction and discharge ports on top of
compressor, drain lubricant from compressor.
(5) Add system capacity minus the capacity of
components that have not been replaced. Refer to the
A/C Component Refrigerant Oil Capacities chart
above. Add lubricant through the suction and dis-
charge ports on compressor. This is not to exceed 150
ml. (5.00 oz.) in total.
(6) Install compressor and connect refrigerant
lines. Then evacuate and charge refrigerant system.
(7) Most reclaim/recycling equipment will measure
the lubricant being removed. This amount of lubri-
cant should be added back to the system. If a new
compressor is being installed, drain lubricant from
old compressor, measure the amount drained and dis-
card old lubricant. Drain the lubricant from the new
compressor into a clean container. Return the
amount of lubricant measured from the old compres-
sor, plus the amount reclaimed from the system back
into the new compressor.