QuestionI recently hit a deer and of course it took out the radiator & A/C condenser. Because I was not going to be able to work on it for a few weeks I disconnected the lines and sealed them up to keep moisture out. I could not find out exactly how much oil I needed to add back into the system when I repaired it, but the tech at a local Ford dealer said if the condenser burst then I lost "all" the oil and charge, and suggested I add 4 oz. of oil.
I found no evidence of oil being discharged from the A/C break. The engine stopped immediately on impact because the ignition wires got cut, so I'm guessing that most of the loss was freon, not oil.
I got a used condenser from a yard and cleaned it out with air and spot checked it for dirt, all seemed OK.
I only added about 3 oz. of oil into the system when I evacuated it. There was no vacuum leak and I initially charged it and the pressures were 35 low and 220 high side. It blew cold for about two weeks then it started blowing cool and the compressor started cycling on & off. Ambient pressure is 100 and running pressure is 25-35 low and 220 high, but as the compressor runs longer the high side get up to 300-325, low stays about the same and the line past the expansion valve start getting warm instead of cold.
I think the cycling is due to the pressure dropping on low side while the pressure on the high side goes too high.
This leads me to several new questions:
1. Could I have a blockage somewhere or maybe too much oil in the system?
2. How do you flush the system and what do you use to flush it out? Is there a reliable way I can to this without taking it to a shop?
3. Could this problem be caused by excessive moisture that cannot be absorbed in the accumulator causing a blockage in the evaporator or the orifice tube?
4. When you take a system apart it is suggested that you always replace the o rings. Since these are all new, if I take the system apart again, do I really need to replace them since they are less than a month old?
5. Thinking I might have too much oil in the system, I pressed the Schrader valve on the low side to see what the mixture was like. It came out really frothy like I mixed oil in a blender. Is this normal, or should the mixture be more gaseous and only a slightly oily feel?
AnswerIn a case such as this you should have installed only 2 ounces of oil in the condensor.
Your problem is most likely foreign debris that has accumulated within the orifice tube. Either remove it and clean it out or replace it, Evacuate the system with a vacuum pump and recharge the system with the exact amount of freon as stated on the sticker and you should be ok.
You should be OK with the "O" rings and it is normal for the oil/freon mixture to be frothy.
