A/C Compressor Oil.

[Matt93eg]

I'll post this up and see what kind of feedback I get, I've been searching around but can't find anything that's exactly my situation.

I just pulled out all the R12 A/C components out of my 93 Civic. Then replaced them with R134a components. This includes everything, all the lines, evaporator, Compressor, Condenser, etc. I got all the parts from one guy that came off a 95 Civic EX, only parts he didn't have were the Condenser and High Pressure hose that runs from the Condenser to the Compressor.

I cleaned the lines up and now have everything installed. The compressor was turned upside down and all the oil drained out and the ports were plugged to prevent contamination of debris. Problem is I don't have any idea how much oil came out. So I don't know how much to put in.

Everything is used except for a new Expansion Valve and Drier. I was hoping to add oil today and pull a vacuum on the system.

Any idea how many Ounces of PAG 46 oil I need to add? I know if I add to much or to little that the compressor will be ruined. I just don't know how much to use.

Following my search it seems you need to know how much oil came out of the old compressor and subtract that amount from how much the total system holds which makes some sense, but I don't know how much came out.

I know A/C help is hard to get around here sometimes but its worth a shot.

Thanks in advance for any insight/help.

[Cynical 1]

about 4 oz of oil is good. a little more (like an ounce) isn't going to kill the compressor, as it will just lie in your condensor or dryer...

also add a little uv dye- in case you get a leak in the future...

[Matt93eg]

Cynical, Thanks for the help. So even though the Condenser and Evaporator I am using are used and most likely still contain some oil, it will still be ok to put 4oz of oil into the compressor? Just checking to make sure I understand you. Also I have read where when you install the new drier you need to add oil to the drier, any insight on this. Thanks a bunch man, much appreciated.

Matt.

[97twodoor]

Yeah i know what you mean. Honda is vague on how much to add to the compressor when replacing it. Here is a bit of a chart for component capacities.
Refrigerant Oil Capacity:
Condenser: 20 ml (2/3 fl.oz, 0.7 imp.oz)
Evaporator: 45 ml (1 1/2 fl.oz, 1.6 imp.oz)
Line or hose: 10 ml (1/3 fl.oz, 0.4 imp.oz)
Receiver/Dryer: 10 ml (1/3 fl.oz, 0.4 imp.oz)
Leakage repair: 25 ml (5/6 fl.oz, 0.9 imp.oz)
Compressor: For compressor replacement, subtract the volume of oil drained from the removed compressor from 120 ml (4 fl.oz, 4.2 imp.oz), and drain the calculated volume of oil from the new compressor. 120 ml (4 fl.oz, 4.2 imp.oz) - Volume of removed compressor = Volume to drain from new compressor.

I also highly recmommend replacing the drier. The drier has a desiccant in it which absorbs moisture. I also would recommend using Ester oil with UV dye in it. Ester oil will mix with the R12 oil that could be left in the sytem where as PAG oil will not mix.

[Matt93eg]

97twodoor, Thanks for the response and info. Nice to see a breakdown on the oil. I did replace the drier with a new unit and also replaced the expansion valve. No need for me to use Esther oil as I am using all R134a A/C parts now. I ripped all the R12 stuff out.

I vacuumed the system down yesterday for an hour and got it to 28InHg. Let it hold that over night until noon-ish today and it still was sitting on 28InHg, no vacuum leaks. So I charged her up. Very happy with the result. Drove around for a awhile and she was putting out nice 38 degree air at the Vents. Very much enjoying the A/C.

[1 Civic I]

Is the AC compressor oil the actual freon or is it something totally different? sorry if this is a noob question. trying to do a compressor project. 1st time.

Did some research and im thinking its an oil and different then the r12 or r134a stuff. ( im using r134a)

[turismoviper]

I'm dealing with this very issue currently in my 96 EK. My compressor is completely dry - so I'll probably be adding 4oz. However, I replaced the dryer as well so I guess I'll be adding more?

However, my question is this:
Do I add the oil directly to the dryer somehow? If so where (I'd imagine where either of the hard lines connect)? If it's not to be added to the dryer directly, do you add it to the compressor and the system eventually moves 'X' amount of oil through the system to the dryer?

As for the compressor - which opening does the oil go in (right or left)?

[dem0nk1d]

Originally Posted by turismoviper

I'm dealing with this very issue currently in my 96 EK. My compressor is completely dry - so I'll probably be adding 4oz. However, I replaced the dryer as well so I guess I'll be adding more?

However, my question is this:
Do I add the oil directly to the dryer somehow? If so where (I'd imagine where either of the hard lines connect)? If it's not to be added to the dryer directly, do you add it to the compressor and the system eventually moves 'X' amount of oil through the system to the dryer?

As for the compressor - which opening does the oil go in (right or left)?

BUMP

[deschlong]

Hi all,

Pretty sure I have all the answers for the questions posed in this thread so far. I just completed a complete A/C retrofit and I struggled for a long time with very similar questions. The questions posed in this thread are essentially they are as follows:

1. How much / what kind / where to add oil for a total R134a A/C retrofit?
2. How much oil to add if you are replacing a component?
3. Do you add oil to the component directly, or do you add it to the compressor? Which port/opening? What if the compressor is being replaced too?

Honda really is vague on a few of these points, and the first one in particular.

Answers:

1. The oil capacity of an R134a compressor is 120 to 140 ml. This info is hidden well in the 94-95 service manual. If you read the original A/C install instructions (available online) you'll also see that at no time do they ADD the oil to the system in a separate step. This is because it is already pre-loaded in the compressor. There is no other sealed unit in the install components, and since the oil cannot be exposed to air, that means all the oil is located in the compressor originally. The oil then travels through the lines and to the various other components on its own once you turn it on. I figured these details out on my own through deduction. Still, I wish I had found this thread earlier - it would have saved me a lot of grief.
   
   The oil used on a 92-95 Civic is PAG46. This info is not found at all in the service manual, but if you look up what oil to use in the NAPA parts finder (or other such databases) you come up with this answer.
   
   If you're doing a complete retrofit of all replacement components, you don't need to bother measuring how much oil is removed from the compressor. Just remove it ALL. Tip it upside down to drain for a long time. Then, when everything's ready to go and installed, add the 120 to 140 ml, dividing the amount equally between the high and low side ports, before hooking on the hoses. Should be the last thing you do before you close the system and pull a vacuum.
   
   
2. The list above in post #4 is correct when replacing a single or multiple components (but not a whole system). If you have done a cabin filter retrofit and replaced the evap component, reduce the added oil from recommended 45 to 40 ml (more compact system).
   
   
3. You can add the oil to the component directly OR you can add it to the compressor. I really don't think it matters. If I had the compressor open, I would add it all there just for ease of access, once again, dividing the amount between high and low ports.
   
   The user in post #7 says they will add 4oz/120 ml to a completely dry compressor, and then more to the dryer. Without getting into the issues that would cause a dry compressor (ie., this shouldn't happen and may be indicative of a larger problem), if I was refilling an empty compressor AND replacing a dryer, I still wouldn't add MORE than 120 ml to the system, since I probably still have oil in the lines and I wouldn't want to overfill. This can go all in the compressor, or the amount listed above in post #4 could be added directly to the dryer, and I would reduce the amount added to the compressor by the same.

[dem0nk1d]

well i'm just reinstalling the system. i've cleaned out all the a/c lines, evap, condenser, installing a new thermal valve, and drier. I then need to button everything up and install the oil directly to the compressor. The compressor has been drained, not an ounce of oil left in it.

So i guess i'll i need to do is button everything up and divid the 4 oz into the compressor. 2 oz on the high and 2oz on the low. Then take it into a show to have it pressure tested and charged. Also replacing all o-rings with new ones. Lube with ester or PAG46 oil. I've heard 5oz will work too.

[deschlong]

^ Yes, sounds about right. You can also do the vacuuming and re-charge at home. I *really* want to encourage the use of Duracool or another R12a-type hydrocarbon refrigerant product as an alternative. They are *really* easy to work with, it's quite safe, and blows colder than R134a. I am *very* happy with it.

[dem0nk1d]

I'm stuck with the R134A system so there is no converting to R12. As long as it's better than my current system, which is 80 mph with the windows rolled down.

NO places around me rent the vac. So i'll take it in to get charged.

[deschlong]

Not R12 ... it's "R12a" ... ie, hydrocarbon refrigerant replacement for R134a. Duracool is an example, and here's a DIY install for a similar product on a Toyota.

But ... if you can't get a vac, I guess you should just go get it charged with the regular stuff.

[dem0nk1d]

Yeah you need a really good vac and a set of gauges, so for me buying everything would cost me more in the long run. Now if i did this sh** every week then it would be logical to buying the stuff.

I thought you want zero Hydrocarbons....

[dem0nk1d]

oh damn you pulled up Yota-tech link! Propz i used that site a long time ago to do my 5vz swap into my old 3vz yota. Best mod ever.

[RonJ@HT]

Also go here for some enlightening R12a discussion:

http://www.honda-tech.com/showthread.php?t=2628720

[deschlong]

^ Yeah, there isn't really a lot of intelligent discussion of R12a in that thread; plenty of typical fear-mongering, though, mostly borne of ignorance. Will edit this post later with some better links.

[RonJ@HT]

Originally Posted by deschlong

^ Yeah, there isn't really a lot of intelligent discussion of R12a in that thread; plenty of typical fear-mongering, though, mostly borne of ignorance. Will edit this post later with some better links.

The concern in that thread regarding potential problems with servicing R12a charged systems seems highly relevant. Or has something changed since that thread was posted?