budget builder

iTrader: (3)

https://www.thirdgen.org/forums/tech...onversion.html

I read the above link and This is a task that i will be tackling this winter. My wife wants me to try to keep the ac now that I'm finished with the 350 swap

hey quick rookie question would I have to change any of my fittings, hoses( I know that I might), evap, condenser, or drier or compressor? My car has all the stock ac stuff. I just don't know if the 23year old parts is considered to be any good or there is a way to check. thanx fellas

converting to r134

nothingbutagthn

iTrader: (2)

if i'm not mistaken new o rings is a must and so is completely draining all old refrigerant and oil. make sure hoses are in good condition and replace dryer with a new one. ck rest of system do a good vacuum and you should be good to go.

budget builder

iTrader: (3)

ok ill read up on how to completely drain the entire system i'm sure i can find the info somewhere thx! but not only that but what is better converting to r134 or staying withthe r12? I know that both will require me to change out all the o-rings and I will inspect the hoses and still might have to replace the drier but is there something that I am missing?

88camaroscv6

iTrader: (1)

new orifice too

fasteddi

iTrader: (2)

Whats wrong with the current set up??

r12 is better yes!! You can buy the stuff off ebay or local wholesalers for pretty cheep anymore as no one uses it much, so the price has dropped considerly. R22 is actualy more $$ then R12 even though they still make R22 and havent made R12 since 1992-1994 I cant remember off the top of my head but its arround then..lol


Get a conversion kit as im sure they make them somewhere. It "should" have new o-rings, a orifice(metering device) and also may have hoses with them. I work on big big Hvac-r but the same principals apply.

You would have to recover the R12 thats in it or just discharge it. Its only like 1lbs or so, so its a diminumis amount to EPA standards. The oil would also have to be drained out. Best way to get the most out is to disconnect the fittings on the back of the compressor and then drain out as much as you can though the suction side IIRC.

I take it your going to R134a? Then youd need the POE oil to go with it.

A good tip to make sure after your done that it works right for a long time is to:

Put a vaccum on the system and make sure it holds at under 500 microns for at least 1hr. Then when you charge it go back and leak check it with soapy bubbles. A leak can not leak in a vaccum and then leak under pressure as Ive seen it many times. If you dont have a micron guage then just pull a percect vaccum for about 1hr then let it sit and ensure it is still there a few hrs later.

Sorry im in no way a Mvac guy so some of the conversions kits may not have what I think they should...lol

budget builder

iTrader: (3)

the current STOCK setup is as far as I know in perfect condition. Now it does not work as far as putting out cold air in any shape, fasion, or form. but all the pieces are there and attached in STOCK form I was wondering exactly how would I test each component to make sure what I needed to buy new. from what I have found out the prices of the parts are pretty close to:

new condenser= $90
new compressor= 170
new hoses=35
new drier=25
new evap=210
o-rings=

this is just in case I need these parts but how do I check them?

fasteddi

iTrader: (2)

The compressor works right? The clutch locks up and spins good?

I would guess that your lost the charge and thats why it doesnt blow any conditioned air.

The way to check them is to leak test it. I.E charge it with dry nitrogen or even some refrigerent if you dont mind spending some$$. I would bet that you just have a bad seal or a cracked tube somewhere. Once there is pressure in the system. 100psi is what I would do... then spray soapy bubbles everwhere and look for the leak.

How long has it been like this? Theres going to be a ton of moisture in your system and moisture+ref=acid. Which is no good. But its nothing a new filter dryer and pulling a good vaccum cant fix.

I would bet that if you get on one of the shrader ports on the system and have it a quck poke with a screwdriver to see if theres anything in it....there would be none. Keep in mind ref is dangerous so make sure you have saftey glasses on when you do this. It could blind you if you shoot just a little in your eyes.

budget builder

iTrader: (3)

I boght the car like this and have had it for 3yrs and have done nothing to or for the ac I did ddo a 350 swap and took loose the hoses on the compressor and have just bolted them back up.

honestly the components LOOK to be in good condition and now I'm glad that I did not destroy the ac stuff b/c the more I learn the more do-able this appears to be as for the compressor cycling I dont know I never really tried it but I know the compressor was unhooked b/c of the swap. I'll take pics tonight.

sofakingdom

iTrader: (1)

New evap = you don't need it if it doesn't have a leak (pressure test it)
New cond = the same thing
New O-rings = about $5 a pound, and there's ALOT of em in a pound, and you only need about 8

If you're converting one of these systems, about the only way to GUARANTEE success, involes REPLACING the compressor and accumulator (which also serves as the dryer). Reason being, the R-12 oil is COMPLETELY incompatible with R-134a (turns to an acidic jelly), and even if those parts are in perfect working condition, it's impossible (or at least, highly impractical) to get all the oil out, so you might as well just bite off on it and replace em.

I would not put R-12 back in a system today. Reason being, not so much anything about TODAY, but rather, that stuff isn't getting any more common, any cheeeeeper, any eeeeezier to maintain. Sooner or later you're too likely to end up right back where you are right now except you won't be able to find something you need for it. (oil is likely to be the first thing that will vanish forever) Might as well RENEW the system with a refrigerant that has some degree of a future, make the system PERFECT (my favorite word!!) in the process, and simplify your life in this one small matter FOREVER.

ringo234

3 cans of R12 $50 plus $8 shipping must send proof you are EPA certified.

nothingbutagthn

iTrader: (2)

This is a pretty good guide right here to follow. When we did conversions at the dealer this is pretty much what we did. When we first did conversions we were recommending replacing the hoses because we thought the 134 molecules would permeate through the hoses, today we know that is not true. I guess you could replace the compressor, but I have never heard of that and personally I think it would be an unnecessary expense. An ac compressor is made up of valves and a piston. Refrigerant is pulled into the compressor, as a gas, on the down stroke, and pushed out of the compressor on the stroke. There are two valves that open and close accordingly. The compressor itself does not know if the gas is r12 or 134a. You pull a good vacuum on the system it will pull all the old refrigerant and oil out so when you add your new stuff ( pag oil and 134a) it will blow as cold and sometimes colder that r12. Some people will argue that but if you ck at the vents with a thermometer it will be very close. Make sure you use 134a and not some of the crap they sell as a substitute.

http://www.autoacforum.com/messagevi...&threadid=7927

sofakingdom

iTrader: (1)

As said, the primary reason for replacing the compressor, is to get rid of the old oil. Oil doesn't evaporate in vacuum and therefore isn't "pulled out" like volatile things are, such as water, solvent, refrigerant, etc. Other than that, there wouldn't be any problem with re-using it; and if you can get that all out of there some other way, such as taking the shell off and tearing it down and washing it all out, then that's another option.

R-134a has a lower specific heat than R-12; that is, it takes less heat energy to raise its temp by some given amount. That means it moves less heat for each pass through the system. It also has a lower heat of vaporization, at the temperatures an AC works at (it's higher at its own boiling point though, making the comparison a little blurry) which is the amount of heat it takes to take a liquid at the boiling point (the highest possible temp of a liquid at whatever pressure), to a gas at the boiling point (the lowest possible temp of a gas at the same pressure). This means that it is less efficient at "getting cold". However in a properly working system, it's usually entirely adequate; and certainly, its other benefits outweigh the minor loss of efficiency.

http://en.wikipedia.org/wiki/Heat_of_vaporization
http://en.wikipedia.org/wiki/Latent_heat
http://web.mit.edu/2.972/www/reports...on_system.html
http://www.learnthermo.com/T1-tutori...son-B/pg05.php

Personally, I have the EPA certification, and can buy whatever I want; not many people do however. This is a further argument in favor of R-134a in spite of its technical inferiority.

nothingbutagthn

iTrader: (2)

Hey sofakingdom you could be 100% correct i hated ac work and therefore didn't really concentrate on it. I knew just enough to get by, but would pass it on for other jobs when i could. I also don't doubt your certs. I'm certified ,but i do concede your probable more knowledgeable than me. The info i gave is only a guideline to go by and what i have done. your way could be better than mine. Just for my conversions i do not replace the compressor.

sofakingdom

iTrader: (1)

As said, if you've got a good way to flush em, which you very well might at a dealership or the like, it's not a problem to re-use em; but for most of us out here in shadetree land though, we don't have a way to do that so there's not much option but to change it out. You're exactly right that the comp doesn't have the foggiest idea which R is in it, the only thing that cares, is the oil. (and the orifice tube to a certain extent)

ringo234

I also have an EPA certification unless they expire?
I've replaced the compressor and cleaned out all the lines,
vacuumed in down twice added leak detector and couldn't find
the leak so I'm replacing the evaporator, condenser. dryer and
orifice tube. So I could go with R12 but I'm going R135A because
it is easier to get now and in the long term. I can get 6 cans on
eBay for less than 3 cans of R12 and R12 is just going to rise no
matter what anyone says.

fasteddi

iTrader: (2)

I have a universal license and no they don't expire. Come to ohio and I'll give you guys some recycled r12.

I will agree that r12 is impractical just because of the fact that the components are not made anymore. This same thing is starting to happen for r22 items. Recycled 12 is cheaper then virgin 22 if you wholesale it. Reason being .... No one wants r12 anymore period unless its in a mvac application.

Anymore you can just buy a EPA card. Although I think its a joke since I had to go to school for it and pay to take a 200 question test through penn state.

ringo234

Well I'm California so Ohio is just wee bit too far.

The shop that I had my compressor rebuilt says the oil
they put in was some new type that was compatible with
both R134A and R12, has anyone heard of this before?
Also since my system leaked as fast I could put the refrigerant
in. I'm now replacing everything do I need to add more oil or not?

nothingbutagthn

iTrader: (2)

They say polyol ester oil is compatible and not as harsh on o rings or seals as pag is. The Poly oil is a retro fit oil. If you are adding oil to a system like topping off you should use whatever oil you have in your system to begin with. In other words do not mix the oils.

ringo234

thanks

budget builder

iTrader: (3)

bump