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1986 AC Recharge

Mar 3, 2001
Andover, MA USA
1986 "Bright Red" Coupe
Does any one know the correct procedure for recharging an AC unit with the newer type refrigerants? I've heard that you need to replace all hoses, o-rings and accumulater/dryer unit before recharging and others say that you only have to change the o-rings and accumulater/dryer unit? I would prefer to do all the mechanical work myself and then bring it to a good shop for charging. Can anyone recomend a good ac shop in the Boston,MA area?
R134a conversion


There is a do-it-yourself kit available for converting your car's A/C from R12 to R134a. Most auto supply stores have it and it is not very expensive. All the instructions come with the kit.

It's easy,
Did you have to change any parts? Accumulator/dryer, hoses or o-rings?
Compressor.. very important


To get the most effective cooling from changing from R12 to R134 be sure to remove as much of the oil from the compressor as humanly possible.. One of most overlooked items in the conversion by shade tree mechanics, and budda is not to get this oil removed.. The conversion done correctly does work. If you don't get all the old oil out of the Compressor you will be disappointed in your airconditioner.. Good Luck

How do you get the oil out of the system? Do you use a vacuum pump or do you remove the compressor and drain?
To do a regrigerant switch over to 134a correctly, you should change: all rubber (hoses, etc), drier, orfice, o-rings, and flush out ALL the oil. If you dont have compatible rubber, then it will start to deteriorate and leak sooner than expected. I have done the conversion and my AC works great. Good luck.
janciello said:
How do you get the oil out of the system? Do you use a vacuum pump or do you remove the compressor and drain?

I hope this doesn't sound to much like a Horses "Donkey", but the answer to both your questions is YES..

Remove the compressor let it drain overnight, most of the oil will drain out. Once everything is back together pull a vacumn before filling with R134. Some shops out here in California WILL NOT use their Air Conditioning equipment to work on old R12 systems. Some shops that still do the R12 WILL NOT work on an R12 Car unless they know the history of it. Seems there is R12 coming across from Mexico that isn't all R12. It is contaiminated with Nitrogen and other gases. The shop we use knows our cars, so I've choosen to stay with R12 until they tell me otherwise. The 81 Corvette gets a complete vacumn and fill every two years. It really isn't necessary but it makes her feel good ;).

The F -12 option

I had a stupid thing happen, I checked my charge in my 88 2 weeks ago and the high side schrader valve has a slow leak, well I forgot to put the cap back on after using my very last can of r-12 to top the system off. and the next day..... all my freon escaped!!!!!! Arrgh.

But a buddy of mine has been working with some new stuff called F-12 ( I'll get the details for you all in a following post )which is "supposed to be 100% compatible" no oil change... no O rings... nuthin'.

We vac'ed the system for 20 min and threw a charge in ( He has a 1989 ) and we compared discharge tempratures (cars on idle 90 deg outside ambient temp 20 min run time)
I was 2 degrees warmer (34 deg.R-12 vs 36 deg.F-12) So I was impressed! but here's the good part 30lb jug
under 200 bucks! WAH HOO!

So... I ve been running cool for 7 days no problems
and you have to change fittings on the high & low sides to make them different than 134 or r 12 fittings and that solved my leak problem from the bad schrader.

Ta Daa!

Thanks for the info about F-12. I had never heard of it, sounds like the answer. Do you know where to get it, along with the valves that need to be changed? Appreciate the help.
I found a bunch of the 1lb cans at my local auto store Bouquet Auto Parts
661-296-8900.... looking into where you can get the 30lb jug


:cool I finally recharged my AC using Interdynamics, Inc. R134a conversion and recharge kit. First vacuumed the system down, held under vacuum for 2 days plus with no leaks. Then recharged the system following the instructions in the kit. Now getting 38 degree air from dash outlets on any setting. Has been working for 3 weeks plus now. Didn't have to open system or replace any parts. No problems so far :cool
I could have saved you a lot of time and money. Mine needed recharging and I went through everything from changing to 134 to having complete system removed and cleaned and put back with 134. Instead I found Enviro-safe freon which is a drop in replacement for R-12. One $6.00 can has my a/c spitting ice cubes out the dash. Heckuva lot better then the $800.00 dollars they wanted to make the system run on 134 which is no where near as good as R-12. And I am a EPA certified MVAC Technician.
For those interested I can give you the email and website where you can, 1) Get yourself some Enviro-safe, 2) take the test and become a EPA Motor Vehicle Air Conditioning Technician for $19.95.
chle93@ptd.net... email for Kit
Enviro-Safe all the info you need
EPA Certificationtake the test and sell 10.00 cans of R-12 for 100.00
R134a conversion didn't cost a lot. R134a conversion kit cost me $29.95 at local BJ's Warehouse. I borrowed a vacuum pump and gauge set. Kit comes with 3 cans of refrigerant, system only used 2 cans of refrigerant from the kit, so I still have an extra can to top off system if there happens to be a small leak. R134a is readily available by the can at Wal-mart or other local parts stores without any licensing required.
Of course the real proof will be how long it continues to function. Winter is approaching here so won't get to use it much in the next 6 months or so.
Thanks for the info on the alternative refrigerants, may become useful in the future.
By becomming an EPA Certified Tech you get the card and become privy to info...be forewarned...you will not be able to buy 134 without a card or someone with a card in the near future. And those with the card also control the price...think about it....
Best bet is go to www.qwik.com and spend the 20 bucks, take the open book 25 question test and be ready for next summer and all the folks that won't be able to buy the stuff over the counter....
Thanks for the advice! I will go for the certificate. Sounds like cheap insurance for future purchases. Doesn't hurt to learn more about doing the job correctly either. I checked out www.qwik.com site. Downloading the 609 manual now. Thanks again.
Well my friend...how did it turn out? Take the test yet?
I took the 609 test today - Yesterday I couldn't spell AC technician, now I are one!!!!!
Thanks for the encouragement.:cool
Congradulations!!!! Now you know about MVAC and can help spread the word on how to take care of the A/C in cars.You will love the nice plastic card they send you....

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