A/C questions

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Beware ;)

Just because your A/C compessor does not come on means its shot. If your low on Freon it want cut on at all. I would find someone that you trust to check to make sure its got enough freon in the system required to work. Also check small stuff like the fuses and the clutch.
 
there should be a pressure activated switch on top of the evaporator (big black steel can on firewall) unplug it, turn on the air, and bridge it with a piece of wire, if the A/C kicks on then you are just low on freon, if it doesnt it might be your A/C clutch, or a relay. All you probably need is some freon though. I would get a cheap walmart 134A conversion kit and recharge that puppy. I bet it'll still blow cold.

Dr.
 
I agree with stinger, car part stores dont know crap about diagnosing problems. Grab the front of the compressor (with the car off) and see if it turns, if you can turn over the front of the compressor (in front of the pully) by hand then chances are there isnt anything wrong with it. But to answer your original question.. No, 5.0's have different compressors, and lines. you will need an entire system from a 5.0 in order to make it work.

Dr.
 
Throwing parts at a problem is not the best way to fix it and testing is free most of the time :)

These parts places are in business to stay in business if you get what I mean. I have been riped off by parts places and mechanics when I was younger and I have since learned to try and do as much as I can on my own. Just try the methoods mentioned and see for your self if the compressor is bad or not because a new compressor is pretty high bux. If the compressor is bad Keep a eye on ebay or your local J/Y for a used one and who knows you may get a pretty good deal ;)
 
Dr_EluSivE said:
All you probably need is some freon though. I would get a cheap walmart 134A conversion kit and recharge that puppy. I bet it'll still blow cold.

Dr.

Except for the fact that to actually convert it requires replacing gaskets, as R134a is much higher pressure than R12 (Freon). You cannot simply dump R134a into an R12 system, this will contaminate the refrigerants and make matters worse. You also need to change the refrigerant oil, as the oil from R12 and that of R134a are completely incompatable. The other problem is that its technically illegal to recharge or even tinker with the refrigerant without EPA certification. Also, if you don't know what you're doing or you don't have the right tools you can do even more damage, such as letting outside air into the freon lines, then you're pretty much screwed; there are reasons why professionals do this.

There are other factors to consider as well, such as leaks. If there is no refrigerant in the lines at all, then the system is contaminated since it has been open to outside air and humidity. The lines will need to be purged, the compressor likely replaced and new coolant added. And then there is the matter of finding and repairing the leak, otherwise it'll just happen again eventually.

Personally, I would either take it to a professional to do the diagnosis and conversion, or see if you have any close buddies in the HVAC field who might be willing to help. Either that or go get certified and learn what you're really doing and be willing to pay about $700 for the tools to properly do the job.
 
SpectralSamurai said:
Except for the fact that to actually convert it requires replacing gaskets, as R134a is much higher pressure than R12 (Freon). You cannot simply dump R134a into an R12 system, this will contaminate the refrigerants and make matters worse. You also need to change the refrigerant oil, as the oil from R12 and that of R134a are completely incompatable. The other problem is that its technically illegal to recharge or even tinker with the refrigerant without EPA certification. Also, if you don't know what you're doing or you don't have the right tools you can do even more damage, such as letting outside air into the freon lines, then you're pretty much screwed; there are reasons why professionals do this.
Yes.... And No. I did my conversion 2 years ago by "donating" my extra R12 to the local A/c shop, then putting in some stopleak & oil and i charged the system with 134A. It has blown Ice cold since then with only a slight (about 6 oz) recharge last summer. You are correct though, to do it correctly you need to replace the lines and O rings, but using the cheap 29.95 Walmart kit i have enjoyed ice cold A/C with virtually No investment compared to the cost of a "real" conversion. You dont need EPA licenses to mess with R134 and its Really cheap compared to fixing it the "right" way. One of these days i will put new lines and Evaporator on. But why fix it if it works?
Dr.
 
Dr_EluSivE said:
Yes.... And No. I did my conversion 2 years ago by "donating" my extra R12 to the local A/c shop, then putting in some stopleak & oil and i charged the system with 134A. It has blown Ice cold since then with only a slight (about 6 oz) recharge last summer. You are correct though, to do it correctly you need to replace the lines and O rings, but using the cheap 29.95 Walmart kit i have enjoyed ice cold A/C with virtually No investment compared to the cost of a "real" conversion. You dont need EPA licenses to mess with R134 and its Really cheap compared to fixing it the "right" way. One of these days i will put new lines and Evaporator on. But why fix it if it works?
Dr.

I'am going on 3 years with my cheap walmart kit with no problems.
 
Dr_EluSivE said:
Yes.... And No. I did my conversion 2 years ago by "donating" my extra R12 to the local A/c shop, then putting in some stopleak & oil and i charged the system with 134A. It has blown Ice cold since then with only a slight (about 6 oz) recharge last summer. You are correct though, to do it correctly you need to replace the lines and O rings, but using the cheap 29.95 Walmart kit i have enjoyed ice cold A/C with virtually No investment compared to the cost of a "real" conversion. You dont need EPA licenses to mess with R134 and its Really cheap compared to fixing it the "right" way. One of these days i will put new lines and Evaporator on. But why fix it if it works?
Dr.

Ah, didn't know they sold a kit. Not to be anal, but, yes, you do need a license to work with R134a. Read the fine print, you do not need a license to buy R134a, however you do need a license to actually charge anything with it or use it (go figure :shrug: ).

On the other hand, if you can find someplace that will accept your R12, the going price is somewhere around $900 per 30# tank for virgin R12. It isn't illegal to buy or sell R12 manufactured before 1997, but it is illegal to do so with R12 made after January 1 1997 (I believe).

Now of course there is always the "its only illegal if you get caught" school of thought, but on the other hand, getting certified will only set you back about $50-100 depending on where you go and if you take the preparation course for the test.

Its your call though, I personally feel most of these laws are BS, but that's just me and unfortunately, BS or not, it is still a law.
 
R134A has no Ozone killing elements in it like R12 has, If you need a certifcation to use it then its probably due to the pressures involved and being trained to safely charge it without blowing yourself up. I was not aware of any permits required for its use. I belive that R12 actually isnt even manufactered anymore and thats why its cost is so high, years ago you could buy cans of it for $2 a #. When i did my conversion i had a shop remove my r12 for recycling and put a vacuum on my system, i think good prep is what has made mine work so well with the conversion.

On a side note, What you may not know is that R12 is actually MUCH heavier than air so when released it falls to the ground and rarely makes it up to the Ozone layer. What is interesting is the fact that the only company that made the substance (DuPont) is the company that pointed out the dangers, and they did so only a few years before their Patent on production was up. When the patent was up it would allow other companys to produce r12 taking away DuPont's Monopoly. However DuPont Came to the Rescue with a New product (R134A) to save the world (and also keep exclusive production rights for refigerant)

Dr.
 
Dr_EluSivE said:
R134A has no Ozone killing elements in it like R12 has, If you need a certifcation to use it then its probably due to the pressures involved and being trained to safely charge it without blowing yourself up. I was not aware of any permits required for its use. I belive that R12 actually isnt even manufactered anymore and thats why its cost is so high, years ago you could buy cans of it for $2 a #. When i did my conversion i had a shop remove my r12 for recycling and put a vacuum on my system, i think good prep is what has made mine work so well with the conversion.

R134a is an HCFC or Hydrochlorofluorocarbon. As a compound it is less harmful to the ozone, but is not completely "harmless" as it still contains chlorine, but the added hydrogen makes it more stable. It is still just a temporary solution until scientists find a "better alternative". As of now, that seems to be R 410A, which is an HFC or Hydrofluorocarbon, which contains no chlorine and therefore harmless to the ozone.

On a side note, What you may not know is that R12 is actually MUCH heavier than air so when released it falls to the ground and rarely makes it up to the Ozone layer. What is interesting is the fact that the only company that made the substance (DuPont) is the company that pointed out the dangers, and they did so only a few years before their Patent on production was up. When the patent was up it would allow other companys to produce r12 taking away DuPont's Monopoly. However DuPont Came to the Rescue with a New product (R134A) to save the world (and also keep exclusive production rights for refigerant)

Dr.

Yes, I did know that. It is also interesting that ground level ozone is the "bad" ozone... and yet, heavier than air R12 is bad for the upper ozone? Yes, I also was aware of the fact that just a few years before DuPont's patent ran out suddenly R12 was horrible for the environment and a "better solution" was required. I almost went into HVAC as a career last year, but it wasn't the right job for me. My dad has been in the field for roughly 4 years now, and I have learned most of this stuff from him. Either way I'm testing for my certification this summer anyway, I would have last year except the school I was testing through was less than helpful in organizing testing.

And to Jason, no problem, glad to help.
 
Stinger said:
People that work at parts stores are morons...I would trust them to tell me if I had a booger on my lip or not.

HEEEEEEEEYYYYYYYYYYYYYYY

Not all of us are un-educated idiots. But I do understand, i work at a parts store and have to deal with other parts stores occasionally, and yes, most of those people are complete idiots. But, then again, it depends where you go. If you go a place that pays $2.00 an hour to their employees what do you expect? :shrug:

Now, on with the A/C question.

If your compressor doesn't kick in it's most likely one of three problems.
1. your system is undercharged, probably caused by a leak.
2. Your Clutch Cycling switch is defective, it's the one located on the accumulator by the firewall.
3. your compressor/clutch is defective.

both 1. and 2. can be checked by disconnecting the plug going to the cycling switch and bridgeing the connector.f

Whoever said you have to have a license to work with 134a is absolutey, positively correct, the EPA requires that any work peformed on an automobile air conditioning system be performed by an EPA certified technician. As far as buying the refrigerant, anyone can buy 134a. If you read the fine print this is all mentioned on the back of those cheap Wal-Mart kits.

That cheap Wal-Mart kit is not a good ideal, although it will produce cold air.

When you retrofit, you must change the oil and refrigerant, which the kit does. What most people don't know is that you also must change the filter/drier. The dessicant in the accumulator isn't compatible with 134a. The dessicant won't remove moisture from the system and will result in the system becoming comtaminated with moisture, 134a + moisture = acid. This can take a while depending on the system, so some people have no problem with the Wal-Mart kits, but you will sooner or later and when it fails it will hit the pocketbook hard.

Also, when you retrofit, R134a operated at slightly different pressures than R12. with R12 30lbs of pressure meant that the refrigerant was at about 30 degrees. with 134a 30 lbs of pressure will equal about 35 to 40 degrees.

Sooo, you know that little switch we were talking about on the accumulator/can on the firewall? guess what, since it's calibrated to kick the compressor out at 32deg with R12, it actually kicks out at about 40 to 45 with 134a. a retrofit switch is available for this. I have retrofitted a lot of vehicles with great success, as long as you don't try to go cheap, this doesn't work on A/C work, spend the money do it right and enjoy for years.

This is one of the reasons that most people say 134a doesn't cool well in an R12 system, and some it won't because of condensor design.

It's illegal to top off a system and keep going, if the system is low, the EPA states that you must repair the leak, not top it off every year.

I have all the proof for this and will gladly post it here if you like, in addition read my signature i'm certified to work on auto a/c systems and have been doing it for a while now.

any more questions? :D
 
Actually, I should have mentioned this in my first post, but there is actually no belt on the a/c, but I can turn it with my hand. Someone mentioned that if i could do that, it wasn't bad. I am not sure why they told me that it was broke, they probably didn't even check it since the belt was off.
How hard is it to put the belt on? I don't know too much, is it possible to do myself with the right tools? After I put the belt on, is there a good next step?
Thanks again for all your input.
 
SpectralSamurai said:
Read the fine print, you do not need a license to buy R134a, however you do need a license to actually charge anything with it or use it (go figure :shrug: ).

to buy handgun ammo you have to be 21..but if its for a rifle you only have to be 18..so i always buy .40 cal rifle ammo, and shoot it through my glock :rolleyes: