A/C Questions
Thread Starter
Racer
Joined: Jun 2008
Posts: 319
Likes: 5
From: Justin Texas
A/C Questions
I punched a small hole in the A/C condenser of my 93 and have a new one coming. 
The system was working fine before the screw-up. My questions are; With a completely empty system, how many cans (12 Oz) of R-12 should it take to re-charge the system? Do I need to add oil? If so, how do I know how much is there and how much to add?
Thanks in advance for your help. It's damned hot here in Texas this week and I need air.
The system was working fine before the screw-up. My questions are; With a completely empty system, how many cans (12 Oz) of R-12 should it take to re-charge the system? Do I need to add oil? If so, how do I know how much is there and how much to add?Thanks in advance for your help. It's damned hot here in Texas this week and I need air.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Fill should be on the Blower Motor Housing so follow that.
Assuming it wasn't a massive, golf ball sized leak, all the oil should be in it. Get a new Accumulator and when you take out the old one, drain and measure what's in it; add that back plus 1 ounce (which will account for any losses and anything coating the inside of the old Condensor which you will never get anything out of).
Assuming it wasn't a massive, golf ball sized leak, all the oil should be in it. Get a new Accumulator and when you take out the old one, drain and measure what's in it; add that back plus 1 ounce (which will account for any losses and anything coating the inside of the old Condensor which you will never get anything out of).
Thread Starter
Racer
Joined: Jun 2008
Posts: 319
Likes: 5
From: Justin Texas
Thanks. I should be able to take it from there. It just has a small pin hole at the top of the condenser - it fogged up the garage pretty good though. I had not thought of changing the accumulator. Thanks again.
Thread Starter
Racer
Joined: Jun 2008
Posts: 319
Likes: 5
From: Justin Texas
More Help
I finally got the condenser changed. What a B..ch!
It was suggested that changing the accumulator was a good idea while I have it apart and that adding oil was accomplished by draining the oil from the accumulator and replacing the same amount + an ounce in the new accumulator.
Although the old accumulator feels like there is something inside that moves when you shake it, nothing comes out - certainly no oil. The old and new look identical but the new one is 7.7 oz. lighter than the old one - which would tend to indicate there is something inside the old one. Filter element, absorbant material?????
At this point, I am wishing I had just taken the damned thing and had someone do it - that knows what they are doing - but, I'm way down the road with freon, gauges, oil etc.
Since there is no oil draining from the accumulator, should I just add an ounce of oil -by pouring it in before reinstalling the accumulator - and go on? Also, I'm assuming the orifice on the accumulator is the "low side" connection.
Any help will be GREATLY appreciated.
It was suggested that changing the accumulator was a good idea while I have it apart and that adding oil was accomplished by draining the oil from the accumulator and replacing the same amount + an ounce in the new accumulator.
Although the old accumulator feels like there is something inside that moves when you shake it, nothing comes out - certainly no oil. The old and new look identical but the new one is 7.7 oz. lighter than the old one - which would tend to indicate there is something inside the old one. Filter element, absorbant material?????
At this point, I am wishing I had just taken the damned thing and had someone do it - that knows what they are doing - but, I'm way down the road with freon, gauges, oil etc.
Since there is no oil draining from the accumulator, should I just add an ounce of oil -by pouring it in before reinstalling the accumulator - and go on? Also, I'm assuming the orifice on the accumulator is the "low side" connection.
Any help will be GREATLY appreciated.
Burning Brakes
Joined: Feb 2009
Posts: 785
Likes: 3
From: Richmond Virginia
The difference in weight is the moisture and oil absorbed and clinging to the desiccant bag (which you're hearing moving inside the old accumulator) The new accumulator calls for 3.5 ozs and 1 oz in the condenser. The entire system holds around 8 oz IIRC. If you didn't add to the condenser I'd add 4.5-5.0 ozs and you'll be fine.
BTW just read ALL of your post the orifice tube is located in the high side (smaller of the 2 pipes) inlet side of the evaporator.
BTW just read ALL of your post the orifice tube is located in the high side (smaller of the 2 pipes) inlet side of the evaporator.
Last edited by TWISTERUP; Jul 3, 2011 at 08:02 AM.
Thread Starter
Racer
Joined: Jun 2008
Posts: 319
Likes: 5
From: Justin Texas
After viewing a bunch of "how to" on You Tube, I came to the same conclusion as you about the desicant in the accumulator. Also figured the best way to service the oil was to remove the compressor. Good thing I did. There was less than an ounce of oil in the compressor. The manual at AutoZone said the compressor would hold 8 oz. but, the stamp on the back said six - and, that was all it would hold. Got it all back to gether and getting ready to vacuum it down and discovered that the shrader valve on the high side has a quick disconnect adapter - so off to AutoZone.
Thanks for your help. As usual, this group is a gold mine of information.
Thanks for your help. As usual, this group is a gold mine of information.
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
NO!!!! 8 ozs is system capacity and it's carried with the refrigerant to lube the compressor. Generally, most rests in the Accumulator. You could dump 4 ozs of oil in a new compressor with a complete system rebuild and put another 4 ozs in the Accumulator; but that isn't what you're doing. Your system had 8 ozs in it when you holed the Condenser, and it probably had close to that when you replaced it. I'd put no more than 3 or 4 ozs in the new accumulator - or if you want to, flush the compressor by putting in a couple of ozs, turning the shaft a dozen or so times in one direction, then the other. Dump and repeat and leave a couple of ozs in it and put a couple of ozs in the new Accumulator, but I wouldn't add more than 4 ozs to the System unless you're going to flush everything and start over (which unfortunately is the only way to really know it's got the right amount).
Thread Starter
Racer
Joined: Jun 2008
Posts: 319
Likes: 5
From: Justin Texas
I don't know how much oil blew out when I punctured the condenser - it was a pretty spectaculer fog (I may have single handedly brought on massive global warming) - but, there was not a drop from the accumulator when I removed it and, less than an ounce from the compressor.
After I replaced the accumulator and condenser and drained the compressor, how much could be left in the system? I ended up putting about 6 ounces in the compressor after I rotated it about 6 times by hand.
Do you think I need to disassemble it and drain some from the compressor or, will it pump through the system when it's started up?
After I replaced the accumulator and condenser and drained the compressor, how much could be left in the system? I ended up putting about 6 ounces in the compressor after I rotated it about 6 times by hand.
Do you think I need to disassemble it and drain some from the compressor or, will it pump through the system when it's started up?
Burning Brakes
Joined: Feb 2009
Posts: 785
Likes: 3
From: Richmond Virginia
I don't know how much oil blew out when I punctured the condenser - it was a pretty spectaculer fog (I may have single handedly brought on massive global warming) - but, there was not a drop from the accumulator when I removed it and, less than an ounce from the compressor.
After I replaced the accumulator and condenser and drained the compressor, how much could be left in the system? I ended up putting about 6 ounces in the compressor after I rotated it about 6 times by hand.
Do you think I need to disassemble it and drain some from the compressor or, will it pump through the system when it's started up?
After I replaced the accumulator and condenser and drained the compressor, how much could be left in the system? I ended up putting about 6 ounces in the compressor after I rotated it about 6 times by hand.
Do you think I need to disassemble it and drain some from the compressor or, will it pump through the system when it's started up?
Thread Starter
Racer
Joined: Jun 2008
Posts: 319
Likes: 5
From: Justin Texas
Next (Goat Rope) Issue
IMO if you didn't add oil to to the accumulator or condenser you will be fine and no I personally would not disassemble-period. The oil will mix with the R-12 and get to the accumulator-condenser etc. Entire system spec. is 8oz.--1 or 2 ozs. over will not hurt you. Cars I've seen with to much oil and not cooling properly usually had 15-16 ozs of oil and were overcharged w/R-12 or R-134 to boot. They usually had a small seasonal leak (like a evaporator) and every time they (owner or tech) "topped' the system off so to speak they also added 2-3 oz. of oil. Once again do what you're comfortable with, but i don't think 6 oz in the compressor will hurt you.
The gauges I borrowed are for R12. When I went to hook up, I discovered - what I assume to be the high side shrader valve - has been replaced with a quick disconnect. I have maintenance records on the car from date of purchase. No record of it being upgraded to R134. Maintenance records from the previous owner indicate the ECM and AC pressure cycling switch were replaced in 2003 for AC not cooling.
I bought an R134 Quick Disconnect adapter for the high side but, that doesn't fit either. It won't slide all the way down on the shrader.
Picture of the shrader/quick disconnect on the high side.
Another View.
Picture of the shrader on the accumulator/low side - normal R-12. The guage connector screws on to this one OK.
This thing has been a frustrating goat rope from the beginning. Or, it could just be my lack of talent/ability.
Burning Brakes
Joined: Feb 2009
Posts: 785
Likes: 3
From: Richmond Virginia
Thanks for the input. I really don't want to take the compressor and accumulator back off again.
The gauges I borrowed are for R12. When I went to hook up, I discovered - what I assume to be the high side shrader valve - has been replaced with a quick disconnect. I have maintenance records on the car from date of purchase. No record of it being upgraded to R134. Maintenance records from the previous owner indicate the ECM and AC pressure cycling switch were replaced in 2003 for AC not cooling.
I bought an R134 Quick Disconnect adapter for the high side but, that doesn't fit either. It won't slide all the way down on the shrader.
Picture of the shrader/quick disconnect on the high side.
Another View.
Picture of the shrader on the accumulator/low side - normal R-12. The guage connector screws on to this one OK.
This thing has been a frustrating goat rope from the beginning. Or, it could just be my lack of talent/ability.
The gauges I borrowed are for R12. When I went to hook up, I discovered - what I assume to be the high side shrader valve - has been replaced with a quick disconnect. I have maintenance records on the car from date of purchase. No record of it being upgraded to R134. Maintenance records from the previous owner indicate the ECM and AC pressure cycling switch were replaced in 2003 for AC not cooling.
I bought an R134 Quick Disconnect adapter for the high side but, that doesn't fit either. It won't slide all the way down on the shrader.
Picture of the shrader/quick disconnect on the high side.
Another View.
Picture of the shrader on the accumulator/low side - normal R-12. The guage connector screws on to this one OK.
This thing has been a frustrating goat rope from the beginning. Or, it could just be my lack of talent/ability.
R-134 quick connect for gauges and internal threads for the cap
R-12 external threads for gauges and cap
If it was me since you're going back w/R-12 and using mineral oil-I'd try to remove adapter/fitting from the high side (be sure there is a schrader valve in the fitting which is made on the line) and then use the R-12 gauges you have with out the quick connect to Evac. and Recharge
I'm thinking the high side adapter in the pic is a R-134 conversion from a Auto Zone-Advance-Pep Boys etc.==the conversions i've done at dealers were approved by the factory and came with a sticker which said the system was converted and the correct R-134 caps so there were two ways for someone to recognize it had been converted. What you have looks like it would use the R-12 caps. I'm wondering also if the quick connect adapter you bought is actually for the low side ??
Last edited by TWISTERUP; Jul 3, 2011 at 07:39 PM.
Thread Starter
Racer
Joined: Jun 2008
Posts: 319
Likes: 5
From: Justin Texas
[/QUOTE]
If it was me since you're going back w/R-12 and using mineral oil-I'd try to remove adapter/fitting from the high side (be sure there is a schrader valve in the fitting which is made on the line) and then use the R-12 gauges you have with out the quick connect to Evac. and Recharge[/QUOTE]
I made a half hearted attempt to get it out but, was afraid I would break the line. I may give it another go tomorrow. I'll need to get a replacement schrader valve on Tuesday.
If it was me since you're going back w/R-12 and using mineral oil-I'd try to remove adapter/fitting from the high side (be sure there is a schrader valve in the fitting which is made on the line) and then use the R-12 gauges you have with out the quick connect to Evac. and Recharge[/QUOTE]
I made a half hearted attempt to get it out but, was afraid I would break the line. I may give it another go tomorrow. I'll need to get a replacement schrader valve on Tuesday.
Burning Brakes
Joined: Feb 2009
Posts: 785
Likes: 3
From: Richmond Virginia
If it was me since you're going back w/R-12 and using mineral oil-I'd try to remove adapter/fitting from the high side (be sure there is a schrader valve in the fitting which is made on the line) and then use the R-12 gauges you have with out the quick connect to Evac. and Recharge[/QUOTE]
I made a half hearted attempt to get it out but, was afraid I would break the line. I may give it another go tomorrow. I'll need to get a replacement schrader valve on Tuesday.[/QUOTE]
If you're unable to unscrew the R-134 adapter from the high side line-it can be left alone. Since charging is done thru the accumulator (low side) that hose from the gauges can be used alone to recharge. The down side is you won't know as you're charging what the high readings are. However as opposed to breaking and replacing the line I'd do the evacuation and recharge using just the low side connection.
I made a half hearted attempt to get it out but, was afraid I would break the line. I may give it another go tomorrow. I'll need to get a replacement schrader valve on Tuesday.[/QUOTE]
If you're unable to unscrew the R-134 adapter from the high side line-it can be left alone. Since charging is done thru the accumulator (low side) that hose from the gauges can be used alone to recharge. The down side is you won't know as you're charging what the high readings are. However as opposed to breaking and replacing the line I'd do the evacuation and recharge using just the low side connection.
Melting Slicks
Joined: Jan 2009
Posts: 3,482
Likes: 196
From: folsom california
Too much freon; too little oil could lead to a compressor failure. I'd price out a new compressor and a new clutch. Then I'd weigh that cost against the cost of taking it to a shop. It could be an expensive learning curve otherwise.
