Maxthe7man

The air entering the condensor is not 170 degrees now is it... Guess I should also add that standard hi pressure cut out for r-12 and r-134a systems is generally 180 psi, so it would never run at the pressures seen at 170 deg..Max

While I am at it, I should add the best way to stop the compressor shaft seal from leaking, is to run the a/c at least once a month regardless of the season...If you find the leak at the shaft seal, don't run out and buy a new compressor right away, charge it, run it, 99.9% of them seal up with oil...
I have run r-134a on mineral oil systems even in low temp applications, where the piping run was short, with no problems... I can't say enough about a good evacuation with POE though, its a total must...
Don't charge to a full glass at idle with the hood open on a cool day, you will overcharge the system, its best to wiegh in the charge, but if you don't have a capable scale, charge with the engine running at least 1200-1500 rpm, leave the hood down,and add small amounts of gas periodically checking for a level in the glass... at Low rpms, the condenser is WAY to big for the system so people tend to flood it when charging at idle resulting in high head conditions and reduced performance at cruise speeds... High head due to overcharging also shows up on your engines temp gauge in warm climates...
After you put the caps back on the access fittings for the system, spray them with soap, they like to stick and seep after charging....Max

J-Rat

iTrader: (2)

Its not the compressor I had an issue with (and several others). Its the High pressure lines not holding up. Last year and the year before (and this year too), you will hear about people putting 134A in thier systems and blowing up thier high pressure lines.

Now, you maintain that R134a is fine.. Good! And you have experience, even better!

I will never do it again, and all I have is my personal experience to go by. And my limited knowledge of AC systems.

Maxthe7man

Again its not the gas, its the technique of people using it....

Digi7ech

iTrader: (1)

I have heard the key to a successful 134a swap is a complete cleaning of the old 12 before putting the 134a in.

We did it on my buddies chevy pickup and it took us like 40 minutes since we sucked it all out and ran a cleaner or something through it to remove the extra stuff like you said(the POE or whatever).

Then we filled it up w/ 143a and the thing damn cold.

J-Rat

iTrader: (2)

Okay, I will conceed...

Now, how about you keep helping out with the AC thread? Are there are any other glaring inaccuracies that you see?

Cloud

It'd be nice to list some good places and part numbers for those of us that DO need to replace a few parts...if someone has already done the research, please post up!

Maxthe7man

I am not sure about the r-12 drop in blends sold in the US, but there were a few here that had butane in them and they are quite dangerous...
Some drop ins that have a flammable component that are ok are 406a and 416b, I have not been able to make those refrigerants burn with an open flame..
Mp-39 works ok in cars.. 409a likes to seperate in systems while they are running, which gives the txv a hard time when metering the refrigerant...
Rapid compressor cycling when fully charged, with low suction, and cold expansion valve, dirty evap or bad evap motor, or plugged heater coil...
Rapid cylcing with full charge, and warm suction, bad metering device or plugged drier..
Some times pressure switches go bad as well though..
When you have to heat exchangers in a row like in a vehicle where you have a heater core, then an a/c evap, the dirt all ways seems to make it through the first exchanger and stick on the face of the second due to lower air veloclity, so even if the first exchanger is clean, check the second ones surface, its probably plugged there...
Another charging tip, if the vehicle is red hot inside, don't fill the glass with a red hot car, the txv is wide open, and you will overcharge the system trying to fill the glass on a hot car, let it come down to at least 78 before you go filling the glass on the reciever...Max

mwpayne

I just bought some freeze 12 on ebay from "Frosty-Freeze", also ordered and put in a small can of the stop-leak (system was blowing warm, cold last year). The thing is I have no idea how much to put in..would a set of guages tell me? I'm clueless in this area.
I put in 1 small can on my 88, 2 cans in my 84.
Did I do good? They're both cold now.

Scott 89t2

AC is for ******

gsracer

says the canadian who has year round A/C outside

SBi_Owner

There is no "DROP-IN" replacement charge in the US for R12. I have done HFC-135a convertions with mutch sucess but the actual convertion is upwards of $140 complete with new seals, reciever, oil, charge, orifice and misc parts. Most of the products I use come from Mainstream Engineering.

Maxthe7man

hfc-135...hmm.....

SBi_Owner

Ok, here we go, a list of coolants here in US.

Methane Series
R10, R11, R12, R12B1, R12B2, R13, R13B1, R14, R20, R21, R22, R22B1, R23, R30, R30B1, R31, R32, R40, R41, R50

ETHANE SERIES
110, 111, 112, 112A, 113, 113A, 114, 114A, 114B2, 115, 116, 120, 121, 122, 112A, 122B, 123, 123A, 123B, 124, 124A, 125, 130, 130A, 131, 131A, 131B, 132, 132A, 132B, 132C, 133, 133A, 133B, 134, 134A, 140, 140A, 141, 141A, 141B, 142, 142A, 142B, 143, 143A, 150, 150A, 151, 151A, 152, 152A, 160, 161, 170

PROPANE SERIES
216, 216A, 216B, 216C, 218, 290, C316, C317, C318, 600, 600A, 610, 611, 630, 631, 702, 704, 717, 718, 720, 728, 729, 732, 740, 744, 744A, 764, 1112A, 1113, 1114, 1120, 1130, 1132A, 1140, 1141, 1150, 1270

ZEOTROPES
400, 401, 402, 404, 407, 410

AZEOTROPES
500, 501, 502, 503, 504, 505, 506, 507

ALOT OF THESE MAY OR MAY NOT BE PURCHASED BASED ON AVAILABILITY. I DO NOT SEE R135........

BronzeDuck

Back to the top. Hope thisll do its job.

rs_1101

how do i install ac in my car!? i found what looks like a condenser in front of my radiator.. ummmm did my car have ac? can i put it back?

JackoliciousLegs

JRAT, can you post a writeup of how to recharge a barely leaking A/C system with stop-leak and freeze12?

J-Rat

iTrader: (2)

Sure, give me a few...

SBi_Owner

Back to the top!!!!!!

J-Rat

iTrader: (2)

I have never really used stop leak, and from what I know, stop leak (or anything else you add to your system that doesnt need to be there), will decrease your systems ability to cool (takes up more space in the reciever/accumulator). Plenty of people make R12 compatible stop leak though... If you want to go that route.

Charging it requires a pressure gauge and some refrigerant. Optimally, you want a setup that charges the system while you monitor the pressures... I am ghetto, I just add refrigerant, then recheck the pressures (what can I say... ). You add coolant to the "low pressure line" using the dispenser provided for whatever refrigerant you choose (different refrigerants have different fittings to prevent co-mingling).

Keep adding refrigerant till your running pressures are around 30-40 PSI (The EXACT figure is in the haynes and the FSM)..

You ONLY add refrigerant when the system is running and the thermostat is FULL COLD.

DISCLAIMER:

If you blow yourself up because you made a boo boo, dont come crying to me. I learned this all on my own, and I dont consider myself to be the all knowing guru. I just know that I have personally built and charged over 5 systems now, and they still work.. Take that for what its worth..... Plus I hate giving those bloodsucking auto repair shops one damn dime of mine...

duehuynh

forewords: I am not an AC expert, just a skeptic!

I have no working AC in my 87T2, and in GA, you NEED AC in the summer. Thus, the little lady sits in the garage for most of the summer.

Awhile back, I started to do some research on R12 alternatives. I went to several forums for AC techs, and the underlining theme I got from all the readings is that none are really work LONG TERM; somehow each causes problems to the system sooner or later. But it seems some MAY be better than others.

I am going to dig back and see if I can find those articles. Meanwhile, here are two to start:

http://www.yarchive.net/ac/r406a.html

http://www.autofrost.com/autodisc.pdf

duehuynh

some more info:

http://www.ackits.com/testresults/alttest.pdf

the AC forum:

http://www.ackits.com/forum/index.cf...=Yes&forumid=1

duehuynh

Max/j-rat:

Let's say you don't have 12V at the compressor, is it a good idea to by-pass the switch for a sec to see if the compressor runs? If so, for our car, how do you do this?

thx.

J-Rat

iTrader: (2)

Ive done it for Troubleshooting purposes only. Not generally an advisable practice, as the high/low switch is there for a reason.

There is a single wire that runs to the compressor, thats your 12V for your clutch. Just run a 12 V wire from the battery to the connector on the AC compressor. You should hear the clutch engage. That should be a quick 30 second test to see if the Compressor is dead, or you have problems elsewhere...

duehuynh

no one has input regarding fr12 vs autofrost?

J-Rat

iTrader: (2)

Can we get this sticked or archived or something?