Discussion
I need to recharge the air conditioning system in my 1986 289i. Can anyone tell me the amount of freon specified? I want to do the recharge by weight and cannot find the information in the engine bay where it should be, or elsewhere for that matter. I intend to convert from R12 to Duracool. Does anyone have experience making the change?
Hi mate...I used to own a Saab that had R12 refrigerant in the system and couldn't find anyone at the time to re-fill it..(1994)..R12 is mineral oil based and the R134a is synthetic based, They cannot be mixed.
I looked into a conversion but most of the hoses and components would of had to of been replaced which started to get expensive, I should imagine it would be the same.
If you are lucky then you might be able to still find a licensed technician who can re-fill the system but they are few and far between now.
There are also complications/Laws as to leakages or potential contamination from ruptured lines in the event of an accident..
"Save the ozone"..Bag a cow.....
Look what i found on flea...
http://www.google.co.uk/url?sa=t&rct=j&q=&...
I looked into a conversion but most of the hoses and components would of had to of been replaced which started to get expensive, I should imagine it would be the same.
If you are lucky then you might be able to still find a licensed technician who can re-fill the system but they are few and far between now.
There are also complications/Laws as to leakages or potential contamination from ruptured lines in the event of an accident..
"Save the ozone"..Bag a cow.....
Look what i found on flea...
http://www.google.co.uk/url?sa=t&rct=j&q=&...
Edited by mrzigazaga on Monday 3rd February 09:44
There does not appear to be a chart for the 280 AC system.
High side pressure/amb temp/humidity.
Sooo....choose a low humidity day, not too difficult in your location
Fit a new Drier.
Then vac down to zero, about five minutes, let it sit, the needle should not move.
Then vac it down again, just leave it for an hour.
Start engine switch on AC (and fan)
Attach can of ref to your gauges and open low side, the comp solenoid should operate almost immediately.
Low side should move lower if you manually blip throttle and be around 30 when pulling.
Continue adding ref until the high side gauge shows about 260.
That should be enough as the engine is only on idle.
The low side metal part of the hose should be super cool with condensation on it.
Two cans may be enough, but buy three.
For the AC to work well you will probably need to put shut offs in the heater hoses as I found just pushing the heater control to off was not sufficient to completely stop the flow of hot coolant.
Much easier than changing the temp reg which is hidden.
Duracool is flamable.
R12 is not generally available, but visit a few car shows, chat to a few people etc etc.
Going rate so I'm told is 50 bucks a can.
High side pressure/amb temp/humidity.
Sooo....choose a low humidity day, not too difficult in your location
Fit a new Drier.
Then vac down to zero, about five minutes, let it sit, the needle should not move.
Then vac it down again, just leave it for an hour.
Start engine switch on AC (and fan)
Attach can of ref to your gauges and open low side, the comp solenoid should operate almost immediately.
Low side should move lower if you manually blip throttle and be around 30 when pulling.
Continue adding ref until the high side gauge shows about 260.
That should be enough as the engine is only on idle.
The low side metal part of the hose should be super cool with condensation on it.
Two cans may be enough, but buy three.
For the AC to work well you will probably need to put shut offs in the heater hoses as I found just pushing the heater control to off was not sufficient to completely stop the flow of hot coolant.
Much easier than changing the temp reg which is hidden.
Duracool is flamable.
R12 is not generally available, but visit a few car shows, chat to a few people etc etc.
Going rate so I'm told is 50 bucks a can.
Thank you for all the great info.
I won't put any additional R12 into the atmosphere, but I am considering R12a. I found that R12a, which is essentially what Duracool is, is a highly refined form of butane. While it is flammable, it is much more stable than butane. There are enough drafts in my TVR that there is little chance of butane collecting. If I go this route, I'll post the results back here.
Arizona is a place where air conditioning is very desirable.
I won't put any additional R12 into the atmosphere, but I am considering R12a. I found that R12a, which is essentially what Duracool is, is a highly refined form of butane. While it is flammable, it is much more stable than butane. There are enough drafts in my TVR that there is little chance of butane collecting. If I go this route, I'll post the results back here.
Arizona is a place where air conditioning is very desirable.
Good choice to stick with R12 as the system was designed for it.
Different molecule size to 134a and all that.
I assume you will get a Mech shop to do it.
Don't open the system if you don't need to prior to taking it in.
If you change the drier (advisable) you may need to buy a "stubby" as it's a bit of a tight fit in my 85. Yours looks like an 86 so maybe drier size is not an issue because of the rad relocation.
Different molecule size to 134a and all that.
I assume you will get a Mech shop to do it.
Don't open the system if you don't need to prior to taking it in.
If you change the drier (advisable) you may need to buy a "stubby" as it's a bit of a tight fit in my 85. Yours looks like an 86 so maybe drier size is not an issue because of the rad relocation.
I recharged my A/C with Duracool. First I pulled a vacuum. It leaked down slightly over about an hour. Since Duracool molecules are supposed to be considerably larger than R12, I went ahead and pulled another vacuum. My gauges are for R134a, so the connectors are too large to both fit on the back of the compressor. Due to the clearance problem, I only used the low side gauge. I added the Duracool per their instructions (inverted can). With a fast idle (about 3,000), I stopped when the low side pulled down to about 25 psi.
With about am 80 degree F ambient, I was getting 54 degrees at the dash vent. It has been about three weeks and the charge has not leaked down. I was out this morning and the A/C was working great! Because of the very limited outlet vents, I suspect that it will not cope well with a 115 degree Arizona day. However, it is working and I am declaring victory. Thank you for the good advice.
With about am 80 degree F ambient, I was getting 54 degrees at the dash vent. It has been about three weeks and the charge has not leaked down. I was out this morning and the A/C was working great! Because of the very limited outlet vents, I suspect that it will not cope well with a 115 degree Arizona day. However, it is working and I am declaring victory. Thank you for the good advice.
Edited by wlkariz on Thursday 6th March 05:55
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