Restoring Air Conditioning

[HondaBoy]

seems like the summer's going to be here soon and bite me in the ass. last summer wasnt too enjoyable, especially with a black interior. so i think this summer i need the a/c in working condition. so pretty much it needs a recharge. i think the compressor still works. the only thing i can remember that was wrong was what i'm guessing was the condensor would leak into the car on the passenger side instead of dripping down under the car. i know thats not good. my friends dad just did a conversion from R12 to R134 in his '93 suburban to the front and rear a/c's. anyone done the R134 conversion to your 3gee? i figure that'd be so much easier to do than to take it to a special shop to get that done. i know a mechanic that has done the R134 conversion to a bunch of old cars. i'd probley want to let him do that. so what do y'all think about fixing my a/c? i personally find it well worth it for summer because temps like to stay up around 95 or higher for the most part.

[AccordEpicenter]

you can use 134a but yeah the compressor needs to be in decent condition and you will most likely need a new condensor too. I dropped my a/c and lines years ago

[mouchyn]

well, if the system was draining water into the car, that tube is just clogged. easy fix.

personally, i would stick with the R-12. If you're creative enough, you can find it cheaply. I bought 5 cans of it for $50 a couple months ago

converting to R-134 on your 3gee will prove to be disappointing unless you do it right. Doing it right is going to cost you a couple hundred bucks and don't let anyone tell you otherwise. It's not just a "change the valves and charge with R134" type deal.

to do it right, you need to remove and replace the shrader valves, get decent brass R-134 fittings (not those cheap aluminum interdynamics sets), replace the dryer, draw a deep vacuum on the system for HOURS, charge with the appropriate oil, and carefull charge with new R-134 using professional gauges.

Going about the conversion any other way is going to result in AC failure either immediately or 6 months from now. Rather than doing it cheaply now and paying for it later, you're better off doing it the right way now and saving yourself the cost of a blown compressor.

if you don't have (or want to buy) professional AC gauges and a vacuum pump, then I would let a shop do the conversion for you. It will be quite a bit more for them to do it right and you can't even be sure they did it right.

FYI: since the R-134 molecules are physically smaller than R12 molecules, the oraphice tube(s) and other parts aren't going to perform at their best. The stock system was designed to accurately flow certain size particles at a certain pressure and velocity. Reducing the size of those particles will drastically change how the system performs and how long it lasts. Generally, the system won't cool as well as an R12 system -- especially when it's hot outside. It you get your converted system down to 50 degrees out of the center vents when it's 90 degrees outside, consider yourself lucky.

You know what texas summers can be like. Here in humidity-ville College Station, AC systems really have to struggle to work efficiently. My R-134 converted 3gee will take about 20 minutes to get down to 50 degrees when it's hot outside. My stock R12 3G prelude gets down to 40 degrees in a matter of seconds no matter how hot it is outside.

check out www.aircondition.com for more information. those pros will help you get the job done right, which ever way you go.

[carotman]

That's really interesting mouchyn. I thought about installing an A/C system on my B20A but the compressor is specific to this engine. Since it's not the same as the A20A, i was wondering if the R134 conversion was possible at all.

[Oldblueaccord]

Look up something called Freeze 12 I used it on one of my old dodges last year is a great replacement for r-12 no need for oil changes etc.

Otherwise r-134a you should change the oil out of the compressor and then do the standard refill procedure moucyn listed. I changed out all my o-rings out when I did mine 9 years ago but I dont think it is necessary. I had a slight leak that used 2-3 cans of 134 a year but I went with the sealer condtioner stuff and so far I'm up to snuff this year. I didn't change any of the scharder valves because my friends guages were r-12 back then. I made a hose with the r-12 on one end and then the r-134 on the other. You can use barb fitting and double clamps it should see more than 40 psi anyway.

The only problems with are r-12 are cost and its illegal, at least here, to use without a liscense. R-134 is diy and so is Freeze 12.

My experience is the compressor clutch goes bad on our cars.


wp

[mouchyn]

Look up something called Freeze 12 I used it on one of my old dodges last year is a great replacement for r-12 no need for oil changes etc.

Otherwise r-134a you should change the oil out of the compressor and then do the standard refill procedure moucyn listed. I changed out all my o-rings out when I did mine 9 years ago but I dont think it is necessary. I had a slight leak that used 2-3 cans of 134 a year but I went with the sealer condtioner stuff and so far I'm up to snuff this year. I didn't change any of the scharder valves because my friends guages were r-12 back then. I made a hose with the r-12 on one end and then the r-134 on the other. You can use barb fitting and double clamps it should see more than 40 psi anyway.

The only problems with are r-12 are cost and its illegal, at least here, to use without a liscense. R-134 is diy and so is Freeze 12.

My experience is the compressor clutch goes bad on our cars.


wp

i can't believe i totally forgot about the o-rings. yes, you need to change all the o-rings when converting to R-134. Some people get lucky/lazy and get away with not changing them, but you're supposed to. Rubber rated for R-12 will still let R-134 out since the R-134 particles are so much smaller.

Freeze 12, however is pretty good stuff. If your system has no pressure (leaked out completely, you discharge it to replace shrader valves, etc), i would still replace the dryer and draw a deep vacuum. That will make sure the system doesn't have any moisture (AC efficiency killer) and you can use the gauges to see if the system has any leaks.

[TheWatcher]

I agree w/ mouchyn, no need to switch from R12 yet, it's still relatively available. Great write up by mouchyn, I just wanted to add a warning based on my personal experience with my 1987 Civic (donated - I loved that car). Battery acid had eaten through a A/C hose below the battery, and I waited too long to replace the A/C. They had to replace a bunch of parts, because they were now "contaminated" (term whoever fixed it used, can't remember if the dealer or my mechanic repaired it). So don't make my mistake, get it fixed as soon as you can.

Peace.

[88Accord-DX]

Good info. mouchyn, nice write up...

[HondaBoy]

i'd heard a lot that R12 is over all more efficent than the newer gas. like the R134 wouldnt be as cold as the R12. i guess thats about right. about that Freeze 12 stuff, i'll have to look into that. i had heard about that a while back but never gave it any thought. maybe that'd be easier to do than the R12? i wanna see if that mechanic had the vacuum machine thing to do a/c's. for the a/c compressor's clutch, that actually might have gone out because when i had a belt on there and would turn the a/c on, it wouldnt catch. at least it didnt seem to. you can usually tell that the engine is under load when the clutch is engauged on the compressor. i'll have to check that out also.

[mouchyn]

if you're having your mechanic do the work for you, i would just find some cheap R-12. You can find it on ebay, but they will only sell it to "licesned AC repair mechanics." Apparently, i'm a licensed AC mechanic, now if you know what i mean

using real R-12 eliminates the possibility of the Freeze12 causing any kind of compatibility issues with any existing R12, thus reducing the engine's efficiency. homogenous mixtures will peform much better than non.

[HondaBoy]

the mechanic i'm thinking of has that certification where he is able to buy the real R12 gas. its just sort of expensive. i guess i'd have him test the whole system before getting the R12 or other gas. the dryer and evaporator arent too terribley expensive. if the compressor is bad, i suppose i can have him rebuild it. or i can probley do that. but hey if i can actually get the R12, that'd be great. i know for a fact it is much colder when compressed than R134. if any of y'all remember the old chevy's, say like from the 80s you know what i mean.

[Oldblueaccord]

the mechanic i'm thinking of has that certification where he is able to buy the real R12 gas. its just sort of expensive. i guess i'd have him test the whole system before getting the R12 or other gas. the dryer and evaporator arent too terribley expensive. if the compressor is bad, i suppose i can have him rebuild it. or i can probley do that. but hey if i can actually get the R12, that'd be great. i know for a fact it is much colder when compressed than R134. if any of y'all remember the old chevy's, say like from the 80s you know what i mean.

The compressor wont come on if the freon is low. It saves the compressor from pulling its own oil out and ruining it. You can jump that switch out with a wire. I think its by the dryer. to test the system.

I have no idea which one is better than the other as far as cooling. I would factor in that as a system ages its losses its efficiency so unless you replace every componet it would be hard to judge. I think our cars have a fairly large system and you would be fine anyway you go.

When I did mine the clutch was as much as the whole compressor but now a days you probably get one pretty cheap. I got mine for a $100 in a junkyard.


wp

[mouchyn]

there's a guy in forth worth texas that sells freshly rebuilt compressors for $150

[nswst8]

I've done the shadetree conversion back in 97 and didn't even flush the system completley.

Now your evaporator drain hole is clogged. Temp fix is to use compressed air to clear the drain hole. Real fix is to remove the evaporator and clean out the housing.

(Condenser is in front of the radiator)

The best compressor seems to be the Keihin since I have had no problems with this one since I bought the car back in 92.

I highly recommend the conversion for cost compared to R12.

Now I have personally recharged A/C that had been down for better than 2 years its taking a chance but to date I have not had the desecant bags fail and clog the system.

Good luck

[DBMaster]

The Keihin compressor holds the nickname "eight year compressor" because that is as long as a brand new one will last. There is a reason Honda dropped it after 1989.

This compressor has seals made of a material called "Viton." It is incompatible with a 134a conversion and will being leaking post haste. I don't know if it is the synthetic A/C oil, or the fact that 134a is a hydrocarbon refrigerant. (yes, it can be flammable under the right conditions) If you have the Denso compressor you might get by for a while. I replaced mine six years ago with the Sanden compressor that Honda offered in a kit along with the hardware, hoses, etc. It still has R12 and works quite well, though nothing beats the A/C I had in my old 72 Pontiac (31 degrees at the center vent)

IF you can stop the leaks and IF you or a friend have an EPA certification stick with R12. I have read up on a replacement called Enviracool. If you want the link PM me as I don't have it bookmarked here at the office. You definitely want to stick with something that has the same or lower head pressure than R12. R134a will not provide satisfactory results for a Texas summer. Of course, anything is better than nothing and if you still have the old Keihin compressor it's living on borrowed time anyway.

[nswst8]

So again, I have to say that if you have one stick with it until it goes.

[DBMaster]

Just don't put 134a in it unless you want it to "go" sooner.

The R12 replacement I was thinking of is actually Autocool.

Here is the URL: http://www.autocool-refrigerants.com/

[Oldblueaccord]

Just don't put 134a in it unless you want it to "go" sooner.

The R12 replacement I was thinking of is actually Autocool.

Here is the URL: http://www.autocool-refrigerants.com/

Thats an intersting statement. Mines been r-134a for almost 10 years now. When do you think it will "go"?
And what will go first so I know what to look for?


wp

[Oldblueaccord]

The Keihin compressor holds the nickname "eight year compressor" because that is as long as a brand new one will last. There is a reason Honda dropped it after 1989.

This compressor has seals made of a material called "Viton." It is incompatible with a 134a conversion and will being leaking post haste. I don't know if it is the synthetic A/C oil, or the fact that 134a is a hydrocarbon refrigerant. (yes, it can be flammable under the right conditions) If you have the Denso compressor you might get by for a while. I replaced mine six years ago with the Sanden compressor that Honda offered in a kit along with the hardware, hoses, etc. It still has R12 and works quite well, though nothing beats the A/C I had in my old 72 Pontiac (31 degrees at the center vent)

IF you can stop the leaks and IF you or a friend have an EPA certification stick with R12. I have read up on a replacement called Enviracool. If you want the link PM me as I don't have it bookmarked here at the office. You definitely want to stick with something that has the same or lower head pressure than R12. R134a will not provide satisfactory results for a Texas summer. Of course, anything is better than nothing and if you still have the old Keihin compressor it's living on borrowed time anyway.

What if I choose to run a little more head pressure?

Im thinking 40 low side 225 high side last I looked at some guages but thats been a long time ago.

"R134a will not provide satisfactory results for a Texas summer" SO what do thet use in Texico to cool cars? Plaese inform me.


wp

[mouchyn]

What if I choose to run a little more head pressure?

Im thinking 40 low side 225 high side last I looked at some guages but thats been a long time ago.

"R134a will not provide satisfactory results for a Texas summer" SO what do thet use in Texico to cool cars? Plaese inform me.


wp

you know they use R-134a. newer cars have parts designed for the smaller 134 gas, though. my mom's 95 celica will drop down to 37 degrees at the center vent in a matter of seconds no matter how hot it is outside. I have NEVER seen that kind of performance out of a 15+ year old retrofitted system. The only way to make these systems get cold like that in a 100+ humid texas summer is to stick with R12 or an R12 compatible gas.

with a retro'd 134 system, 40/225 is kinda high. i would be surprised if that cools well at all. In my 88 LXi, i'm running 27/175 and it blows at 40 degrees at the center vent after just 3 or 4 minutes.

[DBMaster]

OK, guys, let me just say I am not an sir conditioning technician. I have a good amount of experience replacing systems and repairing them. I also have consulted with people who know a lot more about this than I do.

There are numerous references about the Keihin compressor not being suitable for use with R134a. That does not mean that people have not done it and been happy with the results. If it gets a few more years out of your system and you are happy with the performance, more power to you. A/C systems since 1994 have been DESIGNED around the use of R134a. Older systems were not. Some retrofits work better than others based upon the compressor, surface area of the condenser, cooling fan CFM, expansion valve, etc.

So, don't take what anyone here is telling you as gospel truth (that includes me) unless they are an A/C tech. There is a lot of information out there about this if you are willing to do the research. My research led me to the conclusion that I would not be happy with a conversion since I like it COLD and I plan to keep the car until it convinces me otherwise. I don't skimp when it comes to replacement parts and repairs. If you are a destitute college student and you just need to car to last you until you can afford the next one your philosophy may be different. My own opinion is that we have been sold a bill of goods about refrigerants in general and there is an entire industry making money from the confusion.

Also, even brand new factory A/C in different cars have different performance levels. I think you'd be hard pressed to say that the A/C in, say, a brand new PT Cruiser works the same as in a brand new Honda Element. There are just too many variables.

[nswst8]

Its threads like these that give people the much needed information to keep their rides moving.

Just as you are giving your best info, we are too. which is good for everyone to get a good idea of what options are available.

Please don't take it personal, I had no idea that the Sanden compressor was the replacement to the Keihin. Thanks

[Oldblueaccord]

OK, guys, let me just say I am not an sir conditioning technician. I have a good amount of experience replacing systems and repairing them. I also have consulted with people who know a lot more about this than I do.

There are numerous references about the Keihin compressor not being suitable for use with R134a. That does not mean that people have not done it and been happy with the results. If it gets a few more years out of your system and you are happy with the performance, more power to you. A/C systems since 1994 have been DESIGNED around the use of R134a. Older systems were not. Some retrofits work better than others based upon the compressor, surface area of the condenser, cooling fan CFM, expansion valve, etc.

So, don't take what anyone here is telling you as gospel truth (that includes me) unless they are an A/C tech. There is a lot of information out there about this if you are willing to do the research. My research led me to the conclusion that I would not be happy with a conversion since I like it COLD and I plan to keep the car until it convinces me otherwise. I don't skimp when it comes to replacement parts and repairs. If you are a destitute college student and you just need to car to last you until you can afford the next one your philosophy may be different. My own opinion is that we have been sold a bill of goods about refrigerants in general and there is an entire industry making money from the confusion.

Also, even brand new factory A/C in different cars have different performance levels. I think you'd be hard pressed to say that the A/C in, say, a brand new PT Cruiser works the same as in a brand new Honda Element. There are just too many variables.

Very well said. Thankyou for explaining more about your previous statements.


wp

[Oldblueaccord]

Its threads like these that give people the much needed information to keep their rides moving.

Just as you are giving your best info, we are too. which is good for everyone to get a good idea of what options are available.

Please don't take it personal, I had no idea that the Sanden compressor was the replacement to the Keihin. Thanks

I took nothing personal. DB made some broad statements that although I disagree with I have no knowledge otherwise then my own that I have AC (134a) and it has been working well since my guess 1995.

I no nothing about viton seals compatibilty other then what I read in MCmaster car last night. I have no opinion either way which molucles are smaller other than I dont think there is any differance seen by a "closed" AC system.

The Sanden compressor was sold I believe as a "retro" kit Honda sold mid -ninteis to help people out that had older systems. And to help, out of your wallet about, $1200 cost. It was recommend to me by my Honda mechanic who tolds me its the only way to go. 4-5 years later he admitted that "ah well you really dont need new hoses and a new compressor" after he realized I had 134a in my car.

Im sure the newer style Honda compresors could be mated to our cars. Maybe from the 4 g accord?


wp

[mouchyn]

Im sure the newer style Honda compresors could be mated to our cars. Maybe from the 4 g accord?


wp

all it takes is a welder and some metal. make a bracket and you can use a compressor from any car you want. The hose connections to the compressor might be different, though.

to fix that, you might have to make an adapter plate at the compressor or crimp on the right connectors.