apie2546

Hey guys,

Ac is the one system I haven't touched in my car. It had a leak when I bought it. Took it to a mechanic and they retrofit it. After it still leaked and they said 1k for a full ac repair.

Went to a shop in the town I go to college, because this Texas heat is killing me. They said the previous shop only installed the valves. They said for $600 they would do the compressor and all other related parts and replace with 134a parts, vacuum and reoil the system, fill with freon and check for leaks.

This is why I do my own repairs. Pain in the *** to do this. Anyway, I'm looking for some advice here. I don't want to spend more money on a non working ac. The old shop did not replace those parts, not sure if it would effect the car running out of freon, however. A full system in my car lasts maybe a day or so.

AlkyIROC

Doing it yourself is fine. You could change parts but to do AC repairs properly, spend the money and take it to a shop. You have no way to nitrogen charge the system to check for leaks and you probably have no way to put the system into a deep vaccum before putting freon back in. Once the freon is back in the system, a freon sniffer can be used to double check for leaks if none were found with a nitrogen charge.

When I switched from R12 to R134A on my 1991 pickup truck, the adapter fittings always leaked so I took the lines off and took them to an AC shop to have R134A fittings silver soldered directly onto the lines where the old R12 fittings were. No more leaks however I did get a leak on one of the line seals on the back of the pump a few years later. Since it was already properly converted to R134A, I took it into the our shop and used the company AC machine to pull the rest of the freon out so I could change the o-ring. Pulled it back into a vaccum and recharged the system. AC worked fine for a few more years until I finally sold the truck.

If you're losing the charge in a day, you have a bad enough leak that it should be detectable with a sniffer or by using nitrogen.

apie2546

That's what I mean, I don't usually mess with ac systems. Too much work and special equipment.
Would an improperly retrofitted system cause a refrigerant leak? They did not replace the compressor or accumulator.Just put the correct fittings on and put 134a

RED85TPI

Hello,

If all they did was put new fittings on your high/low side ports... they didn't do anything. Those fittings are $4.99 at Autozone and all they do is screw on to the old r12 ports. I recently replaced my A/C system. Hoses, compressor, dryer, o-rings and fittings, oil and full system flush... it's not that difficult.

If you're going to spend the money you can buy all the tools (A/c charging manifold, vacuum pump) and all the parts, including the freon, for $450 - $500. And you get to keep the tools! Once you do it, you will be able to charge yours/friends A/C for a fraction of the cost!

Unless you have no time or are not mechanically inclined, of course....

apie2546

I've thought about that for sure, but due to time constraints, its kind of an a pain to have it all done diy style. With two jobs, and one with on call fire department, makes my car really valuable..

What I can see is the accumulator has the fittings and the ac compressor looks original. Maybe new oil. I'm going to buy some leak stuff to find the UV ac leaks to attempt an R and R. I added freon today for a long trip and the compressor is knocking now. Letting the full system circulate it had died down. Think this ac system is on its last leg however..

apie2546

Update.. While driving at night with the ac off, I noticed a fog on my windsheild. Regardless of me opening windows or defrost it immediately refogged.. Leaking evaporator core?

AlkyIROC

Fog on the windshield normally means a leaking heater core but could possibly be a leaking evaporator.

A freon sniffer put into the vents will detect if it's freon or not.

apie2546

Taking it to a place soon. I assume it as freon because I replaced the heater core less than a month ago. And because of the size of the leak. We will see!

jimbear56

Has anyone used the R12a for recharging the A/C?
My 1988 RS still cools some but sure can use some help, and there seems
to be anything local for systems using R12 in them.
Car is RS with 2.8 V6 and approaching 170,000 miles.
any thoughts appreciated

Bubbajones_ya

I've highly considered using R12a, but there is a LOT of debate about the safety of using it, I due to the unavailability of it where I live, I didn't decide to go with it.

With the little research I've done, it seems that other countries, like Canada and some in Europe I believe, have easy access to R12a and its used commonly there (I think especially Canada when I was looking stuff up, because r134a was banned there in 1996.)

In the BEST country, America, (okay I'm being cocky but I really do like this country), R12a isn't legal in every state. I believe the majority of states don't care if it's used, but some states have deemed it illegal to use.

The legality issues are stupid at best I think. People that don't know that much about things and have no engineering background deeming what's legal and what isn't.

_________________________________________________________________
ANYWAYS, to get away from the legality rant...

The REAL issue people bring up is the flammability of R12a. This issue is one that I think has some merit, but is a little overdone.

R12a is a hydrocarbon refrigerant. It's somewhat similar to using propane as a refrigerant source for you AC. The good thing is its completely environmentally friendly, but the bad is that it's very flammable. This sounds like it could pose some pretty serious safety issues if there ever was a leak. Having flammable gasses inside your hot engine bay.. seems a little unsettling.

If you do decide to go with it, I would keep that above info in mind. However, many people have used it and have had no issues at all. And like I said, I know it's much more common in other countries.

___________________________________________________________

Now with my experience with it.

I redid my entire AC system with everything new except the evaporator core. I looked up this R12a stuff and decided to try some.

However, when I was trying to vacuum down my system, it seemed as if there was a leak somewhere so I couldn't give my AC a full charge.

My course of action was to add some UV dye and some refrigerant. Because I thought I was leaking, I only added ONE of the 8OZ bottles of r12a and let the compressor run so I could find a leak.

The AC was blowing really nice and cold with only one bottle for a week. I let it run for a week because I never was able to find the leak so I wanted it to run longer until the dye showed up.

Now.... what I didn't think about was that I was running my system low on refrigerant. Due to this, my compressor overheated and started to smoke and seize up.



Later on, after getting new stuff again, I found out my manifold gauge set was messed up so I could never tell if I had a leak or not. I got a new gauge set and decided to stick with r134a after getting the new stuff, because I would have had to order more r12a online and wait longer to get it. The r134a cools pretty nicely, but the r12a cooled better.







ANWAYS, if you didn't read the entire novel I wrote above:

R12a cools very well, better than r134a, but you should be aware of it's flammability so be careful and make sure you have no leaks. Also, if it concerns you, check if your state says it's legal or not. If you can find it in the auto stores in your state then it's going to be legal to use.

jimbear56

Appreciate the reply/advice and will check availability and legality locally.
As I live close to Canada, may have to go there to get it. I do not think there
is a leak problem as the system has not bee touched since I have owned the
car. Bought it used in 1993, added over a 100,000 miles on the speedo.
Great car for travelling comfortable for long rides, over 800 miles a day,
and very good mileage averaging 28 to 32 MPG with air on.
Thanks again

RBob

iTrader: (1)

I'm using ES-12a, non-flammable and cools better then R12 or R134a. IIRC, three cans even fills our systems.

RBob.

jimbear56

If I use the R12a for re-charge do I have to clear the system of the R12 before or can the R12 and R12a be mixed in system?? I plan going to Canada soon and will try
to get some of the R12a while over there, just not sure as to how much I will need
for the job.

Bubbajones_ya

Well according to Red Tek (the brand that I was going to use and have a little still), you are supposed to evacuate the system.

They do say the R12a is compatible with R12 and R134a, but to evacuate the system regardless.

I'm guessing this has more to do with making sure you have a proper charge than issues with the refrigerants mixing.

R12, R12a, and R134a will all have a different capacity on the systems in our cars. I believe our systems use around 41 ounces of R12, and 85% of that for R134a, then about 50% or so of R12a (compared to R12), but make sure too look up these values before charging because I may be off!!

Whatever you go with, make sure you charge the system with the proper amount. These R4 compressor on our cars can't handle much abuse and an undercharge of refrigerant will quickly overheat and damage the compressor (trust me.... I know.) If you are unsure how much refrigerant you put in, I would err on the side of overcharging, because it will be less strain on your system. Overcharging can start to lower the cooling effects of the system, but undercharging prevents oil from circulating through to cool the compressor.




Anyways, I believe you will only need only around 3 cans of the Red Tek R12a (if that's what you get they are about 6 oz each) acccording to what I remember, but I would probably get 4 to be safe.

mmadden55

R12 and R134 use different composition seals. Go to the AC supply store and tell them you need an O ring assortment for R134 . Might pick up some line wrenches as well. Replace all your O rings. Get someone to vac your ac out and refill with r134, and it would be a good idea to replace your dryer as well when you do the rings. Shouldn't need to do anything else. People who tell you you need to replace the whole system are nuts. What happens is that R134 rots the seals that are designed for r12 and they leak.

I wrote that before I read the windshield part that sounds like an evaporator leak, in which case you need a core and same as above.

apie2546

The two threads are confusing as one I ask for help on 134a lol. Anyway my reasoning behind replacing all the ac components is this,

Its thirty years old, and hasn't had ac in a long time. I'd rather replace it all and it work as efficient as possible and never worry again than to not. Will I see this money back? Nope. But I won't die sweating lol

jimbear56

With "hot" weather hitting this area I decided to add the redtec R12a to my
car's system, air was cool but not cold, added one 6 oz. can and checked
the air flow was pleasantly greeted with cold air flowing from vent's.
Coldest it has been in 10 yrs.
Now I am looking for a lubricant that can be added to system, any thought's
as what will work with the original charge in this 1988 RS with 2.8 v6