AC is working???

[bstan70rr]

I have never heard anyone admit it, and I hope it is not frowned upon, but I was on the B-Bodies only site and could not resist posting the following:

I just finished my year long project of fixing the original air conditioning in my 69 RR. Money and time slowed me down, but I managed to get by without replacing anything inside the car.

Anyway, I am definitely not an AC guy, so I am hoping someone out there can help with the final stages.

I have a constant pressure, so leaks are not an issue.

I put in an 8 oz. can of oil, and there was an additional 1/2 or 1 oz of oil in the first can of freon. I put in three cans of freon, but I am not sure how much the third can was used. The pressure was approaching what I perceive to be the stop level (past that and the gauges told me to "retard")

I did a test run, and it is blowing 53-54 degrees.

I am worried that there may not be enough oil. I cannot drain the freon and check with the dipstick, a process that is outlined in my shop manual.

The manual does say that the original compressor came with 9-10 ozs. of oil, but apparently there could be more in the system. I want to put in another 2 or 3 ounces, but I have no idea how to do that.

Anyone have any suggestions?

If I catch a lot of shit for this, I will not do it again. I promise. BTW, would I be considered a cross poster?

 

[mac]

i am no expert either, but i will give a few suggestions. was the compressor a rebuilt unit and had the oil already in it? did you draw a vacuum on the system which is the correct way to test for leaks? with the vacuum still on the system is when you add the refrigerant. the amount of refrigerant is by weight not volume. gauges only show that the compressor is working properly along with expansion valve. in theory, you could have to much volume of gas or a combination of air and refrigerant that is not efficient enough to work properly. that is why drawing a vacuum and then puting the freon in is important. most cans of refrigerant contain some oil.

 

[A31PKG]

The only way to accurately know what's in there is to have the system professionally evacuated... Is it still R12? If so, it may be tuff to find a shop with R12 equipment... Once the system is evacuated, the recovery equipment will have a drain bottle showing the oil that was removed... This is not ALL the oil, mind you, but just a portion. To know for sure, you would have to drain the components. The compressor and dryer are the largest "vessels" that hold oil, but the condenser and evaporator will as well. In a perfect world the pressures should be about 30 (low side) & 150 (hi-side), with vent temps ranging in the 40's.

 

[ACME A12]

Can't see you catching any sh*t for this... We all frequent other sites and post stuff from them from time to time... Good luck w/ the AC. Sounds like you got some good info from the guys...

 

[69hemibeep]

No crap from me, my Valiant is going to get A/C. To bad your not down here most shops are equipped for R12 still allot of it down here.

 

[A31PKG]

After going through the tech literature, it appears that the system - when new - had 10 to 11 oz of oil from the factory. After initial operation, I am reading that the compressor crankcase oil level should be between 6 and 8 ounces. If we average that to 7, and we average the factory-fill to 10.5, then there should be about 3.5 ounces circulated throughout the system (not including the compressor). Some modern service manuals list the various amounts based upon the component being replaced. For example, if one was replacing a bad condenser one would add "X" amount of oil to the system before recharging. Unfortunately, our FSM does not differentiate these oil amounts... It simply leaves one to "do the math" such as I did above. So....Knowing that there is about 3.5 ounces in the system, one can only estimate the levels in each individual component. The three largest holders of refrigerant oil (excluding the compressor) are the evaporator, condenser, and receiver-dryer. The lines and tubes hold a small amount as well, but would likely be less than an ounce total. From my experience, those larger items should be worth about an ounce apiece... Hopefully this gives you enough ammo to estimate the oil level in your system... Based on your temp readings, as long as the proper amount of refrigerant was used (3 lbs, 6 oz. if memory serves) and the system is otherwise functioning normally, then I would guess that the oil level is too high. Hope this helps!

 

[bstan70rr]

Thanks guys.

It is the R134, and i drew in the refrigerant as you described. I started with the oil and one can of freon to check for leaks. The pressure remained steady, so I said, "what the hell?", and kept on filling her up. Almost three cans later and a short test run got me to blowing in the 50's. I am sure if I would have left it going, it would have gotten into the 40's.

I must have read the same literature as you, and that is why I think I would like to put at least two more ounces of oil in the system. I just do not know how to do that.

 

[A31PKG]

In the absence of a recovery/recharging station, oil can be injected as the system is charged with a special gauge adapter. Also I believe that R143 cans can be purchased with oil already added (you may have mentioned this). The problem is determining exactly how much oil is in the system when your done. In other words, you don't want to overcharge the system in an effort to acheive the proper oil level. It's gonna be a tough one. What are your manifold readings? Also, what are the ambient conditions? Note that R134 gauge readings will be slightly lower than R12. More like 20-25 low, and 130-135 hi.

 

[A31PKG]

Also, another thing worth mentioning when performing R134 conversions, is that any of the old R12 oil remaining in the system will forever stay. This means lower system volume, which means lower system efficiency. Further, just so you understand, the R12 oil and R134 oil do NOT mix... Rather, the R12 oil tends to collect in low-lying areas and just stay there occupying space. Thus, the most effiecient way to perform the conversion is to start fresh by removing all the old R12 oil either through flushing or replacing components. This would include thoroughly draining the compressor.

 

[bstan70rr]

About a year ago, when I started on this project, I flushed the system first. I believe there was some liquid and my air compressor involved. The only old components are a few small hoses and the accumulator. I installed a few new lines, the drier, compressor and condenser.

If I had to do it all over again, I would probably spend all that money on a new conversion unit; however, I am really satisfied with the restoring the original equipment. I just don't want to burn up a new compressor.

 

[Basketcase]

you posted on B Bodies????? time out young man! ( :jester: )

 

[glhcarl]

My air conditioning quits working every time I stop for a red light or stop sign. But was soon as I start moving again it comes right back on? :banana:

 

[69hemibeep]

My air conditioning quits working every time I stop for a red light or stop sign. But was soon as I start moving again it comes right back on? :banana:

most systems are designed to shed the compressor if there is not enough air cooling the condenser it saves the compressor from overheating and blowing off freon. Do you have a shroud and clutch fan? and sometimes the condenser is to small.

 

[Basketcase]

might wanna reread that post Spongey....... :rimshot:

 

[ACME A12]

might wanna reread that post Spongey....... :rimshot:

"Spongey"... :lmao: :lmao: :lmao:

 

[69hemibeep]

might wanna reread that post Spongey....... :rimshot:

I did whats wrong? or did you just want to say Spongey :toetap:

 

[glhcarl]

Spongey? :huh:

I think 'basketcase' was eluding to the fact I don't have air conditioning! :toetap:

 

[Basketcase]

maybe it's a west coast thing. I have the same kinda AC you do. works fine UNTIL The Car STOPS MOVING....waiting a few minutes for this to sink in........ :huh: :acme: :jester:

 

[Basketcase]

Spongey Spongy Spongy :acme: :acme: :acme:

 

[69hemibeep]

:toetap: :toetap: :toetap: :toetap: :toetap: :toetap: :toetap: :facepalm: