AC help

[HondaBoy]

well summer is comming around again and its gettin hot. so i want to try and fix my ac before it gets really hot. ok, so heres the thing, i've converted the system to R134a, sorta. just put the proper oil and gas in, but thats about it plus a new at the time drier. worked last summer, but quit some time ago. holds freon in it, so thats not the problem. its been a while since i did a pressure reading, but they were ok last i checked. what it would do is get cold at the expansion valve, and not into the evaporator. so i'm not real sure if maybe the valve is stuck closed or something like that. i'm thinking to replace the evaporator and expansion valve with a new drier. anyone else had this problem where the cold gas stops at the expansion valve? i'm going to get a vacuum pump sometime soon so i can do this.

also, maybe this could be a bad relay? i dunno, but they dont go out that often. LMK what y'all think on that.

[DBMaster]

There are so many things that could be wrong, including a stuck or clogged expansion valve. Since I used to live where you do now I know that the weather in Corpus from May to October can put quite a strain on a perfect A/C system. For those of you who don't know, we are talking upper 90's with 85% humidity.

I will defer to an expert, but I would try replacing the expansion valve with one designed for R134a and then evacuate and recharge the system. Honestly, you would be far better off with R-12. A business associate picked up six cans for me in Mexico for $2.50 each.

[bushbean]

Is it legal to transport a dozen cans of R12 freon across the Mexican-Texas border without a A/C license?

If so, I think I might make a road trip into Mexico.

Hondaboy,
I think your mistake was converting the system to R134. I've converted two vehicles (Isuzu Trooper and a Mercedes 190E), and the A/C invariably fails after one season. Friends of mine who have done similar conversion also are of the opinion that R134 conversion is a bad idea, and that only do the conversion if you are planning to sell the car. That's why whenever I hear a seller say the A/c has been "upgraded", I assume the A/C will break soon.

[nswst8]

Not a mistake converting to R134a. R12 is just too dam expensive.

Replace expansion valve, no need to replace evap unless you suspect leak/clog (personally I don't think evap is clogged). Just flush evap real good when changing out EV.

Good luck,

[Blkblurr]

I would not put R12 back in it. The fines are too much and it's bad for the environment. Did you measure the temp coming out of your vents with the air off then again after the sir is on? Dioes the copresssor run? Do a pressure measurement again with the ac running.

[LX-incredible]

Replace the expansion valve. Moisture or debris in the system can cause this. I've done several R134 conversions. If it is done right it will last. The dryer should be replaced whenever the system is exposed to the atmosphere. Replacing o-rings and flushing the system is a good idea. When you take the fittings apart you will be susprised how many are leaking. A packet of them is like 8 bucks and has enough for 2 cars.

[nswst8]

When flushing use Denatured Alcohol
put Die Electric grease on o rings prior to reassembly

I would recommend new drier, but I haven't replaced mine since I bought the car in 92 and converted to R134a in 97. I'm playing with fire I just testing a theory.

It still blows cold but the clutch is getting ready to go.

[bushbean]

R134a is bad for the environment too because it is a greenhouse gas that contribute to global warming. My understanding is that scientists are working on a substitute for the R134a.

[HondaBoy]

either way, both gasses arent too great for the air quality. but i'm not real worried about that when i'm sweating like a whore in church on a daily basis. so some denatured alcohol is what to use? i'll try that i guess or i can get the ac flush they have. the expansion valve is about $30, the evaporater and condenser are both over $100. nothing has leaked so far so i dont feel i need to replace anything but the drier. its best to so no moisture is left in the system. i need to get some R134a gauges since i left the R12 fittings and have the gauges for them. and a vacuum pump which isnt very expensive. oh, and some R134a gas. i have some but not enough to fill the system. so, i was still wondering, is the relay listed as the evaporator relay what controls the expansion valve? i found that in the parts available for the ac system.

[nswst8]

Get the Denatured alcohol at Home depot, lowes etc. I will be alot cheaper.

You can rent a vacuum pump Autozone, Advance auto etc.

Don't really need gauges since you are fully depleating the system I usually just estimate it alittle over two 12oz cans I think ours take only 28oz R134a

Unless you just want the hoses and pump like me.

[DBMaster]

OK, a few points here:

R12 is too expensive - I guess that depends upon how much cool air is worth to you. A/C performance in Corpus Christi is never going to be acceptable in a converted system. At the very least you should install a parallel flow condenser along with the conversion. Also, regardless of the gas you use you should fix any leaks in the system.

Importing R12 is illegal - Probably true. The supplier that got it for me is a Mexican citizen and frequently drives back and forth across the border. I also DO have the EPA certification. I have had it since 1994. So, I can buy the stuff legally anyway.

Convert to R134a before you sell the car - You should be ashamed of yourself if you do this. How would you feel if someone did that to you? Better to just sell it and say the A/C does not work.

If I were going to use something other than R12 I would use one of the replacements that runs at pressures closer to R12. Compared to the older auto A/C systems I have worked on even a perfectly functioning 3G system is pretty marginal. It can't hold a candle to a system in an old GM car with the A-6 compressor. 31 degree air and a compressor that lasts forever - that's an A/C system!

[Blkblurr]

OK, a few points here:
R12 is too expensive - I guess that depends upon how much cool air is worth to you. A/C performance in Corpus Christi is never going to be acceptable in a converted system. At the very least you should install a parallel flow condenser along with the conversion. Also, regardless of the gas you use you should fix any leaks in the system.
Importing R12 is illegal - Probably true. The supplier that got it for me is a Mexican citizen and frequently drives back and forth across the border. I also DO have the EPA certification. I have had it since 1994. So, I can buy the stuff legally anyway.
Convert to R134a before you sell the car - You should be ashamed of yourself if you do this. How would you feel if someone did that to you? Better to just sell it and say the A/C does not work.
If I were going to use something other than R12 I would use one of the replacements that runs at pressures closer to R12. Compared to the older auto A/C systems I have worked on even a perfectly functioning 3G system is pretty marginal. It can't hold a candle to a system in an old GM car with the A-6 compressor. 31 degree air and a compressor that lasts forever - that's an A/C system!
I agree with most everything you said with the exception that a GM compressor last forever. My experience has been that they are lucky to make it beyond the warranty period. My neighbor bought a new Buick because she couldn't keep the A/C working and the new Buick was in the shop for 8mo in the first year. One of the problems was the A/C.

[nswst8]

Wow, we have a A/C guru.

No offense intended.

I would love to run R12 but the cost is not an option for most of these guys.

And I've lived in Pensacola and Jacksonville, FL (Humidity as unbearable as Corpus) where R134a was sufficient.

Where can I get a parallel condenser?

[2oodoor]

Something to consider too is upgrading your fans (radiator and condensor) . A higher flowing fan that also pulls less amperage can be made to work with minimal fabrication. Since the 80's , these fans have improved a lot.
I think that may be part of the problem with so so performance with the 3Gee AC systems. The cooler things are up front, the greater heat exchange you will get and thus creat a larger drop in temp from ambient to conditioned air.

I have not done this yet on mine so I dont have any part numbers or models fan you need .

[LX-incredible]

either way, both gasses arent too great for the air quality. but i'm not real worried about that when i'm sweating like a whore in church on a daily basis. so some denatured alcohol is what to use? i'll try that i guess or i can get the ac flush they have. the expansion valve is about $30, the evaporater and condenser are both over $100. nothing has leaked so far so i dont feel i need to replace anything but the drier. its best to so no moisture is left in the system. i need to get some R134a gauges since i left the R12 fittings and have the gauges for them. and a vacuum pump which isnt very expensive. oh, and some R134a gas. i have some but not enough to fill the system. so, i was still wondering, is the relay listed as the evaporator relay what controls the expansion valve? i found that in the parts available for the ac system.

The expansion valve is controlled by the evaporator discharge temperature. There is a sensing probe that comes off of the valve and clips on the discharge of the evaporator The colder it gets, the further it opens. There is another temp sensor that shuts the compressor off when the evaporator gets too cold, but it is not connected with the expansion valve. Make sure that you have the Denso compressor if going with R134, I have heard that the kehin doesn't hold up so well.

[DBMaster]

The Frigidaire compressor to which I referred was not put into GM cars after about 1979. The A-6 was the long, heavy one. You might be referring to the newer ones like the R-4. Those were nowhere near as durable as the A-6. Mine was 18 years olds when I sold the car. The clutch pulley seized up at one point and all I had to do was replace the clutch. It didn't even phase the compressor.

[Blkblurr]

The Frigidaire compressor to which I referred was not put into GM cars after about 1979. The A-6 was the long, heavy one. You might be referring to the newer ones like the R-4. Those were nowhere near as durable as the A-6. Mine was 18 years olds when I sold the car. The clutch pulley seized up at one point and all I had to do was replace the clutch. It didn't even phase the compressor.
It's possible. This Buick was a 1986 Century.

[ahmad89]

i live in houston, tx yesterday the humidty was high and it was just nasty outside, when summer hits it might reach record highs again. My a/c works fine just my idle boost is messed up i think, when im stopped and have the a/c on the rpms are around 500 or less its drops so low sometimes my car shuts off.

[nswst8]

The expansion valve is controlled by the evaporator discharge temperature. There is a sensing probe that comes off of the valve and clips on the discharge of the evaporator The colder it gets, the further it opens. There is another temp sensor that shuts the compressor off when the evaporator gets too cold, but it is not connected with the expansion valve. Make sure that you have the Denso compressor if going with R134, I have heard that the kehin doesn't hold up so well.
I have a Kehin, been converted since 1997.

[MessyHonda]

I have a Kehin, been converted since 1997.


how did you pull that off....i converted my kehin...and it died on me.

[DBMaster]

Everybody gets lucky a few times in their lives. R134a is a hydrocarbon refrigerant, like propane. Supposedly the Viton seals in the Keihin compressor are incompatible with the refrigerant and oil in converted systems. Even though nswst8 has had his last a long time I would not recommend doing it to the Keihin. I would try Freeze-12, or even Propane before I would try that. With either of those you do not have to add new oil.

[2oodoor]

The Frigidaire compressor to which I referred was not put into GM cars after about 1979. The A-6 was the long, heavy one. You might be referring to the newer ones like the R-4. Those were nowhere near as durable as the A-6. Mine was 18 years olds when I sold the car. The clutch pulley seized up at one point and all I had to do was replace the clutch. It didn't even phase the compressor.
those old GM compressors took a lot of power off the engine, one of those would kill a Honda.....
This would be a good place to recommend some part numbers or something that easily replaces the Kelkin compressor on 3g accords, also an improved expansion valve set up....anybody know?

[DBMaster]

Honda itself makes a kit to replace the compressor. I got it put into mine in 1999. The kit includes the compressor (Nippondenso or Sanden), drier, hose assemblies, engine bracket, and belt. This is high dollar. I paid $1,000 including the R12. You can do a search and get an equivalent kit for about $400. This is the way to go for someone like me who plans to keep the car until it does like the Blues Brothers' police car.

Basically, I can afford a new car any time, but I really like this one. So, spending substantial money now and then is OK with me because it's a lot cheaper than payments and I won't do anyting half-assed. If the car ceases to be reliable, or has parts that don't work properly I will get tired of it and want a new one.

[dlr1989]

I'm not trying to highjack this thread but I too have been trying to find an aftermarket compressor conversion option for some time now. After trying to order several different kits that all seem to be discontinued, I discovered that Majestic Honda and a few other places on-line could sell me the actual Honda compressor conversion kit for around $600. Majestic Honda has one of these kits on its way to me right now. I will post an update for those who are intrested on the installation details once I have the kit in hand and installed.

Honda itself makes a kit to replace the compressor. I got it put into mine in 1999. The kit includes the compressor (Nippondenso or Sanden), drier, hose assemblies, engine bracket, and belt. This is high dollar. I paid $1,000 including the R12. You can do a search and get an equivalent kit for about $400. This is the way to go for someone like me who plans to keep the car until it does like the Blues Brothers' police car.

[Blkblurr]

Sounds good. Might help some people on here.

[DBMaster]

I have had this kit on my car since 1999 and it still works fine. Of course, the OEM compressors on our car didn't last mugh longer than eight years so I should keep my fingers crossed once it starts getting really hot here. :)

It hurt a bit paying $1,000 to have it done, but when you factor in the cost of the kit and R12 it was not too bad and it did keep me happy with the car for a good number of years.

It's not like investing good money in a bad car! I look at it as a cost-effective way to avoid new car payments. ;)

[nswst8]

Good information, I guess I did get lucky on mine. Wish I could score the lottery.

I heard alot about freeze12 especially after getting to Texas.

Who sells the Sanden compressors?

[Blkblurr]

I have had this kit on my car since 1999 and it still works fine. Of course, the OEM compressors on our car didn't last mugh longer than eight years so I should keep my fingers crossed once it starts getting really hot here. :)
It hurt a bit paying $1,000 to have it done, but when you factor in the cost of the kit and R12 it was not too bad and it did keep me happy with the car for a good number of years.
It's not like investing good money in a bad car! I look at it as a cost-effective way to avoid new car payments. ;)
That's exactly my thinking. Any money I spend on it is better than a car payment.

[MessyHonda]

just came from Honda....and they did not know of a kit to convert to R134....so yeah where can i get it?

[Vinny]

just came from Honda....and they did not know of a kit to convert to R134....so yeah where can i get it?

http://www.partsamerica.com/ProductDetail.aspx?MfrCode=FAA&MfrPartNumber=65408&PartType=387&PTSet=A

Also, just a casual observation. The napa catalogs say to use ester oil rather than pag in the conversion. I know I've used PAG in the past and I'm on compresoor 3 or 4. Hopefully after I rip everything apart, flush it, and use ester oil it will last more than a season or 2

[dlr1989]

MessyHonda,
Let me begin by apologizing for the long reply I am about to type, again. Ever have a web browser crash:rant: just as you are finishing up a long winded reply...

There are at least two possible conversions to talk about.

First, the compressor conversion. If I remember correctly from earlier in this thread you have the Kehin compressor, as do I. Also as it has been pointed out, the Kehin compress and R134a don't always play together well. I have grown very weary of dealing with A/C problems every year. Those problems have been entirely either directly or indirectly due to the Kehin compressor. So I decided to take more extreme measures this year and began a quest for a different type of compressor. My first thought, and probably the cheapest, was to visit the junk yard and pickup a Nippondenso compressor, mounting hardware, hoses and etc. I also discovered that Honda used two different denso compressors in our vintage Accords. I also discovered several aftermarket compressor conversion kits that use assorted different compressors. These kits come with compressor, mounting, belt, hoses and etc. I also found a message here on 3geez, in fact I found 3geez for the first time while researching this, about an official Honda compressor conversion kit. I think maybe the message was from DBMaster. I sent a question off to Majestic Honda about the Honda kit part number 38020-PJ0-R60 and discovered that Honda still makes the kit, unlike most of the aftermarket ones I found. And the price was not much more though Majestic Honda than I was going to pay locally for a generic aftermarket conversion kit. I now have the Honda kit on order from Majestic Honda and FedEx is scheduled to deliver it in a couple of days. I will try to remember to take some pics and post them for everyones viewing pleasure prior to, during and after installation.

The second conversion is a conversion from R12 to R134a or other refrigerant. Most auto parts stores, even local WalMart, will have basic kits to do this. These kits typically have a few cans of R134a with oil and stop leak, sometimes with a UV dye to help find leaks and instructions. If the A/C system has been opened to the air, like if a compressor and drier/accumulator have been replaced, then the system should be flushed and a vacuum should be pulled on the system to remove the air and moisture and what ever else the vacuum pump can suck out of the system. There are other posts here on 3geez detailing this type of procedure so I won't go into that here.

I suspect that DBMaster would be willing to point out that R134a is may not work out as well as R12 or a few other replacement refrigerants. My opinion is that he would be correct. On the other hand R134a is cheap and easily available and will be my choice to recharge my system after I replace my compressor.

Is the answer to your question covered somewhere in this rather long winded reply?


just came from Honda....and they did not know of a kit to convert to R134....so yeah where can i get it?

[MessyHonda]

MessyHonda,


Is the answer to your question covered somewhere in this rather long winded reply?


well i have a Kehin compressor in my dx but i have a Denso one in my lx-i I will have to talk to my uncle as he converted my dx to R-134 but it died like 4 months later. his shop has all the tools i just dont want to take a crap again. il see if i can replace the pump and see what happens...if it craps out on me again i will just take out the whole system. i dont really need it but its nice to have on hot days.

[DBMaster]

These are the main issues with R134a which made me think hard before deciding to stick with R12.

1. It is a hydrocarbon refrigerant rather than a fluorocarbon like Freon. That
is why you have to use a different type of oil. The OEM oil in R12 systems
will not be carried by R134a and will just "sit" in the low spots.

2. R134a runs at higher normal pressures than R12 so if you put it into an old
system as a solution for a Freon leak you will just leak faster.

3. R134a really needs a condenser with more surface area than ours provides.
It is really not that expensive to switch to a parallel flow condenser, but
why go to the trouble when there are better R12 replacements out there?

If you live somewhere where it is not that hot in the summer you might get by, but I can't imagine being happy in Texas. My experience with this is limited because I have a stash of R12 to keep my system topped off. The cost is not a big issue as I only need to add about a half can every year. It does bug me that I have to add anything, but no detectable leaks were ever found when everything was replaced in 1999.