Do you have to add oil??

[daveleeander]

I am in the process of evacuating the AC system on my '02 XLT. I am going to recharge after seeing if the vacuum holds. My question is since I did not replace any components, just evacuated, do I have to add any oil back in?

Dave

 

[jimcom]

Most refill bottles have like 2oz oil, 10 oz 134a.
Thats what I need to get soon.

 

[daveleeander]

I bought straight 134A. It does not say there is oil in it.

D

 

[prerunner02]

YES pag oil is needed. The ratio is 4.5 oz of pag oil to 1 lb (or 16oz) of 134A

 

[dutch724]

Yes, you need Pag46 oil. 7oz is the total capacity for the fs10 compressor.
At least that is what it calls for in a 93' Explorer.

 

[Brock94]

I disagree with the posts above. Unless you disassemble your system and flush the various components and empty the oil out of the compressor, you can't be sure how much oil is in there already. Some oil will often leak out when you have a leak in the system, but unless the leak is in the right spot, it is likely that most of your oil charge stayed in the system. (Check the system for signs of an oil spot that may indicate the location of a leak.)

If you don't see any signs of oil leakage on the system components, then it's more than likely that you didn't lose your oil charge and don't have to add any. You could probably get away with adding an ounce or two too much oil if you have the factory charge in there, but you should not add 7 oz unless you've flushed your system as stated above.

Too much oil in the system will, at best reduce performance and at worst, it can destroy your compressor by slugging it with liquid oil (liquid does not compress).

.

 

[dutch724]

Brock, I agree with you. I was just saying the max the compressor can hold is 7oz. Thx for straighten it out.

 

[ExplorerDMB]

yeah if you just pulling the freon out and then putting it back...no oil is needed

-Drew

 

[Glacier991]

Well, let me first reassure David and then add my 2 cents. IF your system was fully discharged, and not by a catastrophic loss.... your oil is safely deep in the system and a plain evacuation will not pull any out.

I have a recovery machine, and when I take a charged system and remove the liquid refrigerant, the machine separates oil from the refrigerant. I usually get between 2 to 4 oz out of a fully charged and recovered system. I measure the oil I got out and add new oil back in before I add the new refrigerant.

Maybe I should think of some photo thread to show what I am describing.

 

[jimcom]

A photo thread would be most helpful!