Ive read all the threads I could before doing the convertion, Bought new dryer and orifice tube but I used the blue tube from Ford as someone stated it would cool better everything went well took it and had the R12 evact and there was none then vacumed the system with the Orifice tube and dryer out but when I put it all back together and charged it the compressor didnt turn on till the 2nd can and only for a little while Im on the 3rd can and the compressor only kicked on once in the 3rd can and the psi on the drying is around 45. Why wont it kick on and take more 134 am I missing something? TIA PS Its 90 degrees and Id really like to go to a car show tonite.
R12 to R134 convertion..need help
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Scott Atk
Senior Member
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- May 25, 2001
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You need to vacuum the system with everything in place once you opened the system to put the tube back in you let air in the system, that could be your problem. Vacuum it down again then close off the valves on your gauges and make sure the system holds a vacuum for 15 minutes or so. Good Luck, report back.
p.s. did you add the recommended PAG oil?
p.s. did you add the recommended PAG oil?
I figure it was air in the system but how do I get it out. As for the oil I bought oil but didnt put it in cause the kit had the oil mixed in it said. Im no AC expert but the local shop wanted $250 to $300 and Ive got $60 in it so far and can screw up alot till I give in the the local AC guy. So how can I get the air out with almost 3 cans in it?
Wellllll after going back out to the car it has 0 psi, Thats great. How do I test for a leak?I only changed the dryer and orafice tube so it has to be in those fittings or the new dryer but how do I check for a leak in this? I used new O rings also. Thanks.
YOu should not use the blue tube, as it will cooler better at idle but at 45 mph its going to run hotter vent temps as the compressor is choked.
You need to put a dye in the system and check it with a blacklight to do it properly. However if the leak is huge im sure soapy water on your connections would show as air bubbles instantly. Mayb you pinched the o-rings did you oil them up well? You need about 2.6 lbs in the system to work well.
.If you don't buy a parallel flow condensor its not going to cool very good. especially with a front mount IC.. Expect vent temps to be about 30 degrees cooler than outside air , no cooler.
You need to put a dye in the system and check it with a blacklight to do it properly. However if the leak is huge im sure soapy water on your connections would show as air bubbles instantly. Mayb you pinched the o-rings did you oil them up well? You need about 2.6 lbs in the system to work well.
.If you don't buy a parallel flow condensor its not going to cool very good. especially with a front mount IC.. Expect vent temps to be about 30 degrees cooler than outside air , no cooler.
Sounds like your in over your head, but I think you already knew that. Before you go waste anymore $$$ take it in and have it done right. I am a certified A/C tech (not that that means much), but without the correct equipment to do the job your going to have a very difficult time. When you had the R12 recovered and there was none that means that there was a leak somewhere prior. Scott is also correct, prior to charging the system you need to have it under vacumn to pull the full amount of 134A in, bite the bullet and have it done right. JMO
I bought the "conversion kit" at the zone. Cost about $38 bucks. It came with a gauge, 3 cans of 132a and a couple of fittings. Its 100 deg here and 100% humidity 
It was almost too simple to do, but it's working great. Ididn't change out the dryer or vacuum the system.HTH.
It was almost too simple to do, but it's working great. Ididn't change out the dryer or vacuum the system.HTH.
Jerryl
Tall Unvaccinated Chinese Guy
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- Dec 14, 2004
- Messages
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You can get an AC system vacuum pump at Autozone. They will charge you about $110 and refunfd the $ when you return the unit.TWISTER said:
FWIW ..... I did my conversion about 2 years ago. No oil added, new dryer, new Orifice, new Compressor, flushed the system,. No issues and it works fine. It is really not that difficult, especially if you have done it before. (The GN was the first one I ever did)
Thanks for all the help I just got back from Autozone and they dont have the vacume gauge so thats out I took it apart to check for pinched O rings and nothing, I did use Vasoline when I put them in. The AC had psi before just they said no freon left. I will put the white tube in. The AC hasnt worked for awhile last time I used Freeze 12 and worked for a year then thought it had stopped working and started blowing cold one day. As for taking it to a AC shop Im like alot of you and dont want to leave the car and cant get the time to wait on it. As for over my head, maybe a little but Ive helped alot of people on this board as they have helped me so I never feel that way gotta learn somehow.Im gonna try to charge it again and look for leaks w bubbles if that dont work Ill prolly take it to a shop someday, Just looked easy and If I hadnt changed out the dryer it may have, oh well. Thanks
You can pressure test it with nitrogen-cheap and effective. charge the system to about 125 lbs and if there is a leak you ll find out where it is. then after fixing the leak problem you ll need to evacuate the system again to get any air and noncondensible gases out of the system. hold the system in a vacuum for atleast an hour and if it holds the charge-no more leak. at which time while system is still under a vacuum open the freon into the system until no more will go in-this is a static charge on both the high and low sides which should be about equal pressures on the gauges. once you have done this start your motor ,put the ac on max and see if you can further charge the system to about 35 psi on the suction side, if the compressor doesnt run after starting car then you have to jump out the low pressure switch on the accumulator on the side .a simple jumper wire will do- this will allow the compressor to run so you can pull in enough refrigerant until its fully charged. Also would like to mention that 134A molecules are much smaller than R-12 so it can leak alot faster than R12 did.
ForceFedGN
New Member
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- Sep 24, 2003
- Messages
- 18
On the O-rings you should lubricate them with a little mineral oil, because the R-134A uses a oil that attracts water so what happens over time is that the connections have the possiblity to corrode and become very difficult to loosen up.
Somehow this has become more involved than what I have read about on the subject, You have all been great help but I think I should wait till the AC shop opens on Mon. and ask what they will charge me for what is left to do. I think this may be the best bet. Man I hate letting people work on my car. Im sure some of you do also. I should have just threw some r134 in it and seen what happened but that may have been worse than what I have now. Ill get back to you on Mon and let you know how this turns out. Thanks again for all the help. Marty
A refrigeration engineer may be a bit of an overkill for my problem but thanks for your offer.lol. I build steel buildings and we have a sub contractor that is doing refrigeration on a building right now I may get some help from. may still be easier to have the AC shop do it as not everyone is a car guy.
ODDFIRE6 I live on the MI -IN line in the center of the state. 35 Min from Elkhart 15 minutes from Lagrange. Where are you?
ODDFIRE6 I live on the MI -IN line in the center of the state. 35 Min from Elkhart 15 minutes from Lagrange. Where are you?
JUst remember r-134a is about 20% less efficient than r12 and this will reflect your temps accordingly. The buick regal condenser does not work well with a front mount in front of it. Savanah Air on this site makes a drop in parallel flow condensor and with my testing has dropped the vent temps an average of 5 degrees across the board.
Blown&Injected
Active Member
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- May 31, 2001
- Messages
- 3,721
I bet you had a leak with the 12 and you still have the same leak. the work you did might be good but the evaporator coil may be leaking.
The 134 conversions I have done on several cars (non of'em TR's) has worked great.
If the coil is leaking you will not see the dye - I use a gas sniffer type tester and put it in the vent to test the coil.
The 134 conversions I have done on several cars (non of'em TR's) has worked great.
If the coil is leaking you will not see the dye - I use a gas sniffer type tester and put it in the vent to test the coil.
Sal Lubrano
Active Member
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- Apr 26, 2002
- Messages
- 1,235
Norbs you have a point about less refergerant flowing through due to the smaller orifice but I always use a blue tube on gm retrofits. It produces colder air at idle and I still see 40 degree vents on the highway. Just make sure when you retro-fit to turn the screw to cycle the compressor off at a lower pressure. If you look at the pressure temp chart for 134 it needs a lower pressure to produce the same temps as r-12.
http://www.ackits.com/index.cfm?fuseaction=Chart
I would adjust for it to cycle off at 19-21 psi.
Also make sure you use Ester oil. Do not use pag. Pag does not mix with r-12 residue left in the hoses and becomes corrisive.
Everyone will give you there opinion but you have to make your own decisions.
Here are some great a/c boards.
http://www.autoacforum.com/
http://www.acsource.net/acforum/
Both will recommend using the blue tube on retrofits and POE. Good LUCK
Sal
http://www.ackits.com/index.cfm?fuseaction=Chart
I would adjust for it to cycle off at 19-21 psi.
Also make sure you use Ester oil. Do not use pag. Pag does not mix with r-12 residue left in the hoses and becomes corrisive.
Everyone will give you there opinion but you have to make your own decisions.
Here are some great a/c boards.
http://www.autoacforum.com/
http://www.acsource.net/acforum/
Both will recommend using the blue tube on retrofits and POE. Good LUCK
Sal
