I just replaced A/C discharge line after a having a leak. Since I lost all freon I wanted to add some PAG46 oil back into the system. I ended up using a can with 3 oz of oil/freon/conditioner. I used this first then followed with a 14 oz can of freon. Here is my issue. When I first purged the yellow supply hose to get the atmospheric air out, this released the oil mixture. I used a rag around the fitting so I didn't make a mess but I did not open it for 3 seconds, maybe only 1 second. Was this was sufficient time to get the air out? How is it possible when you have an oil mixture, since more than just gas comes out?

 

the way I do it?

first off, If my system is wide open.. and I need to add oil... i domt just make a habit of slamming 3oz of oil into a system unless i know its suffered a catastrophic los... ie i have found LOTS of oil around the leaking point... and I mean LOTS!..

I usually pour it in directly from a bottle into the accumulator (if there is one).. if there isnt one I put it into the Liquid line....

if im going to add it with a pressurized can, I'll first Vac down the system... if you dont Vacuum down your system solidly after its been open as long as it has with a zero pressure situation its not going to perform very well..

next I attach the oil can / refrigerant mixture RIGHTSIDE UP.. and purge the line slightly with the can rightside up.. this normally gets you straight gas and no oil.. and you just need to crack the valve for less than a second and not fully open.. it doesnt take much to purge the air out going to your gauge set.

then I turn the can upside down and WITH A/C OFF and a completely EMPTY system I release the oil in...

3oz is quite a bit for a blown liquid line.. but i understand you dont want to tear the whole system apart to measure the oil still in it...

after the oil is added, I'll dump full liquid in out of the first can (upside down).. CLOSE the valve.. let it sit for 2-3 minutes, start the car, turn on the A/C and finish my charge up till ive got the specified weight installed or until my Pressures and temperatures Match on the gauges.

-Christopher

 

There is a desiccant bag inside the AC accumulator that absorbs moisture in the refrigerant system. If your system was opened up to atmospheric pressure for more than 20 minutes or so you really should vacuum the entire system for at least a half hour. If it was at atmospheric pressure for more than a day you should replace the accumulator. Just remember, intentionally venting r12/r134 to the atmosphere is a crime and the epa has been known to dish out hefty fines to people they track down on the internets.

 

there is no accumulator on my 2013...... the only 'receiver' is a liquid "catch-all" as part of the condensor itself..


-Christopher

 

There are two pieces of equipment that should be used, a manifold (gauges) and a vacuum pump. The vacuum should run for approx. 30 min. like was previously indicated. Anything else really wouldn't be the best way of taking care of it.

 

Thanks for the responses. I did use a vacuum pump and a manifold to check pressures. The vacuum pump ran for 1 hour and held good negative pressure for over an hour as I checked it. I never added 3 ounce of straight oil. I used a 3 oz can which consisted of 1 oz PAG46, 1 oz of R134a and another ounce of some kind of conditioner. I then followed with straight R134a until I had the correct low side pressure, and good temp from the vent. My only issue had to do with the initial "bleeding" the air out of the supply line to the manifold. When I attempted to do this, the oil mixture shot out first, probably not enough to even be concerned about. It just got me wondering how I was supposed to get the air of the line when there was an oil mixture in it.

 

oil can right side up and then just barely crack the fitting on the manifold till i hear a little hiss and then right closed... thats all it takes.. then you can turn the oil can upside down for the liquid oil and 134a to come out. since you are going into a vacuumed system there will be more than enough 134a and positive pressure in that can to propel the oil into the gauge lines... you dont care if it goes all the way in at this point as you are going to pop a can of 134a on which will push any oil in the gauge lines into the A/C..

-Christopher