A/C conversion successful

[Guest]

That was too easy, had the system evacuated by a shop, then purchased a kit from walmart for around $40 which includes 3 cans of R-134 with oil and leak seal mixed in, and a low side gauge and fittings. 1st. put on the fittings to accomodate the R-134 connections, 2nd. start car, put A/C on high, shake the can real good and hook it up, slowly release the valve with the can tipped upside down. ( at this point, the compressor kicked in and started to short cycle) 3rd. repeat process with the second can, ( compressor now running constant, and you can feel the air getting cool. 4th. Repeat with the third can ( only this time, leave the can upright, and monitor the gauge. Mine swallowed most of 3 cans (45 oz.) including oil and leak fix. Low side pressure was around 38 lbs. at around 850 rpm. Was suprised how cool it is, I've had R134 systems that were not so cool. Now, I just hope that leak fix works good. <img src="http://www.aaca.org/ubbthreads/images/graemlins/wink.gif" alt="" />

[Barney Eaton]

Keep us informed as to the long term performance.

The experts tell us the critical item is to remove all (99%) of the old oil. Most agree that the only way to do this is to flush the system and replace the dryer/accumulator. I don't want to throw cold water on your change-over but depending on the quality of the evacuation, the two oils mixing can cause long term problems.

[Dales90]

Nice explanation of your process. Our only changeover was for my wife's 88 Regal. That car had rubber o-rings from the factory, and the new system needed neoprene. Leaks occured on high pressure side until proper o-rings were installed. (something about the new system lube deteriorating the rubber original rings.)

Dale

[Ken Rosenzweig]

Unfortunately, I paid a lot more than you since I had it done at a Buick dealer. But I had the a/c in my '90 coupe retro-fitted to a non-freon system. It was done just over one year ago, and the system works great. I'd heard that the new systems aren't as effective, but mine is working very well. Even in very hot weather, it doesn't work that hard to keep the car cool.

[CReichert]

Can I ask how much is cost for the shop to do your retrofit on the 90? It's hot in Ohio.

CTR

[Arrallen]

Does anyone know if there is a replacement o-ring kit available for the Reatta, changing them to neoprene?

[Ken Rosenzweig]

It's hot here too.

As usual, dealer labor is ridiculous. It was around $450 for the complete job.

[Guest]

Odds are it may last through the summer? I hope. Probably the difference

with the dealer is that it's a complete job and will hold up long term.

I'll keep you posted.

[Guest DTerry]

For what it's worth, I converted my Dodge Caravan with the 40 dollar kit about three years ago, and other than the slight leak that it already had, it's been trouble free. Same with my old Taurus; three - maybe four - years, and it was still cooling when the clutch failed, just before I gave it away. The conversion kit was one of those things that you never expect: it was just too easy and worked too well. Nothing is ever that easy. My Reatta was converted when I acquired it, and it cools great...when the blower makes up its mind that it's okay to blow today.

[IGottaReatta]

I just had my '89 converted by a local Buick-Pontiac-GMC dealer in South Jersey. Charge was $200 plus tax. This was done just two days ago and weather here has been in the high 80's and low 90's. Air is cold, performance is good.

Also while it was at the dealer's, I had the brakes flushed and filled per forum recommendations. I had no bake problems before, but there is a noticeable difference in pressure and 'road feel'! Well worth the extra charge!

[gearhead]

Maybe I'm just stupid, but I can't get my system to charge properly. I got the same kit you mention at Autozone. Mine doesn't have a pressure gauge like you mention.

I hooked up the fittings and lines like you mention. The kit says to put the oil in first, then the freon. When I hook up the bottle, I can't get the clutch to engage to pump the fluid into the system.

What am I doing wrong? Should I use the freon first, and then the oil? I didn't shake up the can (instructions didn't say anything about that). Don't think my compressor clutch is a problem, because the system worked OK before it ran out of freon.

Can you help me out?

[Guest]

I'm no expert, but I'd disconnect the battery, then reconnect it (will reset the system) then hook up the freon can and turn on the A/C, after the first can, I would put the oil in, then follow with freon. I believe the system wont kick in until it sees some freon, also tilt the cans upside down until the last one. Hope this helps, maybe someone else has some tips. Good luck.

[Guest Greg Ross]

I'd say that makes perfect sense, the compressor has been disabled and the codes that have been set need to be cleared.

[Guest spongebob]

when you guys are doing this change over....are you getting the old oil out of the system?? then adding the new oil or are you just adding more oil??

the compressor wont come on until the low pressure switch has been satisfied..this can be done with a paper clip.(pull conector off and add paper clip)..i love r-12, and wish the previouse owner hadnt done a conversion... <img src="http://www.aaca.org/ubbthreads/images/graemlins/smirk.gif" alt="" />

[harry yarnell]

Nope, Bob, the paper clip trick won't work on the Reatta. The code(s) B446,7,8 must be cleared out of the BCM memory first.

[padgett]

Or jumper 12v directly to the compressor clutch coil...

I believe in flushing and replacing the dryer and oriface tube anytime work like this is done.

Did think the oils were incompatable but 10 years in maybe that problem has been fixed.

[Guest]

People are complaining about the "Freeze-12" costing 3 times more but, it only takes about 3 cans. $18-$20 dollars. Is'nt this better than the conversion to "R-134" costing from $40.00 up to $450.00 ???

[cpu]

I've been reading the Haynes A/C repair manual. Many interesting things in the book. For instance, it's better is some cases to reuse the old R-12 hoses than to buy new hoses that may be intended for R-134a.

Also, time seems to have proven that having some of the old oil in the system after conversion to R-134a is not as detrimental as once thought, particularly if you've replaced some of the components that hold much of the oil (compressor, accumulator...)

[Guest]

Oil compatibility is not an issue anymore..

You should replace all o-rings, orifice tube, and accumulator when retrofitting, and the most important thing is vacuuming the system out - ~29Hg for 45 minutes or so to remove all air/water.

Yes, r-134 is less efficient in Late 80's, early 90's cars, the condensers in our cars aren't as efficient as they could be.

Prperly installed, R134 works well. Remember you need to adjust the pressure cycling switch as well, ~19-21 PSI.

Here's a few good links on R134 basics and conversions. They are from a Turbo Buick Regal site - some details are different, (ability to jumper pressure cycling switch, location of components, etc) and I don't recommend the Venturi-pump type vacuum pump they use, I have one, and unless you have a huge air compressor, it doesn't work well at all.

Conversion Info

R134A Basics

Air conditioning theory

[padgett]

I built a vaccuum (decompressor ?) pump with an electric motor and the vaccuum pump from a '70 GM diesel car (were cluttering up the yards at one point). Pulls as low as my guage will register and I just let it run for a while then shut off, seal, and see it it holds the vaccuum.

Since I do less than one a year this is fine.

Have also heard of old refrigrerator & a/c gutz being converted to vaccuum pump duty.

Even once saw someone just run the compressor with the high side open to evacuate but do not know how much of a vaccuum you can get that way - may be OK in Nevada but not Florida.

Accumulator and oriface tube replacement any time the system is opened but not sure if every O-ring needs unless the system was left open for a while.