AC recharge 88 coupe 130k

[Guest weewilly]

I am looking at a 1988 original owner reatta to buy here in raleigh. an older couple I met said they would sell it to me, after a conversation with them in the lowes home improvement parking lot. The car is not in the best of shape but is a southern car, and I know the history. It has been in there driveway for 2 years with only little use. The question I have is:

The AC does not blow cold , the owners had a new compressor about 18 months ago and it still does not work correctly. I looked at the input valves and it has not been converted to 134. I would like to help them out by recharging with 134 after putting on the correct size input. I tried to but could not get the AC to stay on long enough to intake Freon. What do I need to do to get it to take freon? The computer says it is low on Freon? Do I need to trick the computer for a time to let it take freon?

The other problem is very low gas milage they say about 10 miles per gallon?

That is all that is mechanically wrong except cosmetics. is wr

[Richard S]

Your post may not be a complete description of what you did, so it's hard to give advice. Though most on the forum do not favor the use of a/c sealants, I have had very good success with a product I bought on ebay for my original r-12 system. Now this is where it gets dicey. You say it had not been converted, but you tried to charge it with 134. If I read you litterally, you failed to completely evacuate the r-12 before adding the 134, which is a major no-no. If true, the only thing you can do now is turn it over to the pros for evacuation. You will probably have to replace the dryer as well. Take a look at some of the earlier a/c posts to see what's involved in a proper conversion. If you did evacuate and do a proper conversion from r-12 to 134, and your only problem is that the system is so low the compressor won't stay on, look back in month or so and you will find a very helpful post with a diagram showing where to jumper to by-pass the low pressure switch.

[Guest Mike_s]

I'm no ac expert, but I think if you add 134a to that system it may be a quick fix that could make matters worse.

As I understand it the older R12 systems used mineral oil as a compressor lubricant, mineral oil and 134a do not play well together and eventualy can\will cause problems. R134a requires either POE (ester)oil, POA or endcapped POA oils at the correct viscosity for each application, I think gm compressors use POA 150.

Take a look at http://www.ackits.com/ for info on R134a conversions, and search in this forum for AC topics.

Some folks have reported success with r12 substitutes, but to me they all have issues and most seem to cause more problems than what they're worth in the long run, some contain butane and are highly combustable.

If you buy it and need to repair the ac and /or change to R134a then you might be looking at replacing these parts, pricing can vary depending upon the quality and source.

compressor new, not rebuilt $250-500+

hoses $50-120+

drier,accumulator $15-40+

condensor $100-200+

evaporator ?

orifice $3-30+

134aconversion kit (valves,o rings,oil,lables - $30-50+

cost of drawing a vacume?

flush if warrented ?

[jonlabree]

Unless you find a professional to clean out that system you will continue to have problems.

[Guest Mike_s]

Thanks 63Viking

It seems me flushing is a dammed if you do and dammed if you don't kinda thing. I've read GM does not recommend flushing (edit:with solvents) , because it's difficult to flush certain types of condensers, and mufflers on hoses, that and there's no way to realy check how sucessful the flush was at removing particles from trashed compressors, old oil and the flushing fluid itself. They recommmend replacing parts, while I appreciate their reasoning they are in the parts business.

some of you might find these interesting, from 2001 http://findarticles.com/p/articles/mi_qa3828/is_200104/ai_n8933742/pg_1?tag=artBody;col1

http://www.aa1car.com/library/macs2001.htm (edit)

[jonlabree]

I didn't mean Flush it out. It needs to be Evacuated compltetly and then refilled.

I had the experience with mine. The previous owner (1st owner) either had it filled with the new stuff or had someone do it. I could never get it to really blow cold air. It was cool but not cold. I finaly took it to my Buick dealer because I knew one of the mechamics that really knows Reatta's. In order to evacuate it completly he had to blow it out in the air. The machine that they had kept giving him an error message ans shutting down. They are not supposed to do this but it was the only way to compltely clean it. I have had cold air ever since. 2 1/2 years ago.

[padgett]

I disagree. If you do not know what is in there now, your only choice is a complete flush (with the right flush), evacuate, verify the system holds a vaccuum, and recharge with the proper amount of refrigerant (need less 134 than 12) and oil.

Personally, I'd replace the orifice tube and accumulator as well. With a/c there is no substitute for knowing exactly what is in there.

BTW, disconnect the battery and wait about 30 seconds for the ECM to lose the stored errors and the compressor should spin long enough to insert some freon. The alternative is to wire 12v directly but do not run for long without a proper charge.

[jonlabree]

What are you disagreeing about?

[Guest DTerry]

I bought a kit and converted my old Dodge Caravan to 134 sometime in the last century (at least 10 years and 150,000 miles ago), and it's still cooling well. Converted the Reatta last year - or was it year before last? - and its still cold. I replaced the compressor, drier and expansion valve on the Buick, but on the van I just followed the instructions to replace the 134 and the oil.

What did I do wrong that they're still working?

[Guest Mike_s]

DTterry

Hey, If they're working that's great, maybe they would be working better if other proeedures were done, maybe not,I'm just passing on the consensus of what I read.

On your cars, was there R12 in the system when you added 134a?

It sounded to me as if Weewilly was just going to add 134a to the system without removing the r12, which I still don't think is a good idea.

From EPA http://www.epa.gov/ozone/title6/609/technicians/retrguid.html

"Flushing

The amount of mineral oil that can safely remain in a system after retrofitting, without affecting performance, is still being debated. It was originally thought that any mineral oil left in the system might cause system failure. As long as the tech has removed as much of the old mineral oil as possible, any residual R-12 left in the system should not have a significant effect on the performance of the system. Removing the mineral oil may require draining certain components. Unless the vehicle manufacturer recommends flushing the system during the retrofit procedure, a service tech can assume that flushing is not necessary. (Although the SAE J1661 procedure for retrofit includes flushing, SAE no longer believes that flushing is critical to a successful retrofit."

[Guest Mike_s]

If the refrigerant system is relativly pristeen as in no incorrect oils or sealers were added, or has not had an internal compressor failure I'd give not flushing some consideration.

[Guest DTerry]

Mike,

No, I completely discharged the system before converting. I didn't just add R134 to the R12 already in the system. Don't let the EPA get me, but I just opened the system and let what little that was remaining escape. (horrors!) Followed the instructions and added the proper oil and R134 and presto! Cold air!

[Ronnie]

Dave you bypassed a few of important steps that may or may not come back to haunt you.

1. You should have removed the compressor and drained the old oil and replaced the o-rings when reconnecting.

2. You should have replaced the filter/dryer (sometimes called the accumulator) as it also holds oil.

3. You should have pulled a vacuum on the system to remove any air before refilling.

Some people do as you did and never have a problem. Others will need to replace the compressor after a short period of time. Many used car lots go the route that you did knowing they will only have the car a short time.

[Guest DTerry]

I did all but the evacuation to the Reatta because the compressor was shot. As far as removing the air, I just opened both ends of the system and blew half a can or so of 134 through it.

The Dodge has been cooling great for over 10 years. Incidentally, I sold it last night and the new owner drove away with the windows up and the A/C on.