Now that I've captured your attention...

Well, the situation is looking bad.

Bought the car a few weeks ago...

First off, the compressor clutch was engaging & all seemed fine except for one thing... no cold air.

After a bit of asking around, the idea of recharging with R12 at this point in history is not sounding like a good idea anymore. Pricing we got was rediculous... just for a silly re-charge. We decided to convert to R134.

We bought a Walmart conversion kit. (Probably a bad idea, right?)

We hooked-up the conversion fittings and hooked-up the hose/gage/unpunctured can to check the existing pressure in the system - low pressure port - AC engaged. The pressure was oddly about at zero. Odd because as I mentioned, the compressor clutch WAS engaging. Anybody have an answer for that?

OK, so, we vented the low pressure port & sure enough, just about nothing came out.

We then hooked-up the charging setup, can shook & upside-down, punctured it & let her fill. About 1/2 of the first can caused the gage to rise beyond the recommended final pressure - the "blue" (25-45 psi) sector. It started to go into the "yellow" (45-65 psi) sector, so I shut-off the supply from the can.

Revving the engine caused the needle to drop back into the "blue" sector, but it would go back into the "yellow" sector when the engine was allowed to go back to idle rpm. Still no cold air at all.

So, Haynes manual says to keep filling until the sight glass shows no foamy bubbles & until you get cold air. Throwing a lot of caution to the wind, we went forward with putting more R134 in there.

All of can #1. Not a lot of change, approaching the "red" (65 & beyond psi) sector. No cold air, foaming sight glass.

All of can #2. Still not much a of a change. No cold air, foaming sight glass, gage touching the "red" sector now though. Excursions to 70-75 psi...

Just about all of can #3. Starting to feel some coolness now, just a little. Still very foamy sight glass. Gage parked at about 70 psi or so. Revving still brings it down to the "blue" sector, but right back up into the "red" when returning to idle.

Suddenly, this somewhat loud howling noise started happening. Don't know if it was the compressor. It sounded more in the condensor (radiator) area, but common sense tells me it must have been the compressor. Revving the engine helped quiet down the howling. The howling returned when it went back to idle.

OK, so, the gage was telling me all along that there's too much pressure in there. Now, I'm believing it again. I immediately started venting the crap back out, turning on the AC, howling, back off, more venting, on, howl, off, vent, on, howl, off, vent, on, and so on. Finally, no more howling.

No cold air. Out $35. Found out here, the R134's esther oil combines with the R12's oil to form a sludge. Incompatible O-rings too?

HELP! What do we do now?

btw, cudo's to those of you who remove your AC systems to remove weight. Removal of AC in South Carolina however is not an option... gotta have it, or you die...

Also, the low pressure port valve is oozing yellow foam. (Leaking) I tightened it, but it won't stop oozing.

Common guys, need good help...

 

First, you must first drain the compressor oil and change before the change to R134 compatible lubricant. You are correct they are not compatible. Its not just the rings that will be corroded, the gunk will foul the compressor it self.

Next, the howling you heard was due to air in the system. I had the exact same thing happen to me two summers ago. I had replaced compressors myself but had a Mazda dealer pressure test and charge the system. BTW, I changed both high and low pressure O rings. They were cheap and I suggest you do so as it it is likely they need changing. Get them from Mazda cuz they are two different sizes although it it is actually difficult to see the difference. Paid $125.00 for the service, but they they did not completely vent it. I bet the howling sounded like a very deep trombone with a mute sound. If you had placed your hand on the line coming from the firewall to the reciever. It would be vibrating like nuts. We vented using the tiny bolt on the top of the reciever near the sight glass.

The system holds about 28 oz of refrigerant. If you used more than that to get pressure you were filling faster than an apparent leak. Eventually you will be back to no pressure again.

They key here seems to be the pressure test. You said that there was no pressure but that the clutch as engaging. I am not sure how much pressure if any is necessary for the clutch to engage. But the lack of pressure surely suggested a compromised system. Shops use a halide leak detector before charging. That's a step you neglected.

I suggest you remove the compressor as soon as possible and drain the mineral refrigerant oil and replace with an R134 compatible oil and hope you can save the compressor. Next, even if you want to fill it yourself, go to a shop and have them pressure test it. At the very least they can spot the point(s) where it is leaking. I suspect that you are out the $35.00 you have into it already.

Good luck.

 

Oh come on....
I live in Central Texas. It gets over 100 all the time, and I removed my A/C. Given, it was broken and I was too cheap to fix it, but I never used it on my cars that had it.

 

boobies!? picts!?

EDIT: oh crap...QA for Icemark!

Yellow foam: mmmm umm. Well.. sucks you still don't have A/C. I'd say at this point it might be easier to roll it into a shop and let them deal with the yellow foam Recharges at the shop should only run $100 or so... You might want to mention your R134 stuff prior though.

The loud noise my guess would be the compressure trying to churn that stuff. Second guess is the AC radiator fan.

BTW: I removed all that crap last year, wasn't working anyhow...

 

I would need to drain the R-12 just from the compressor? Wouldn't remnants of it still be throughout the entire system?

What about the weird pressure readings? Could it be that I've had a bad compressor before I even started messing with the A/C? Would an FD compressor mount right in my FC? (It is a R-134 compressor, right?)

Also, does the dryer have to be replaced?

 

#1 You want to drain all the R-12 and R134 ( and oils) from the the system. The R134 is not compatible with the R-12 seals/O rings.

#2 probably the simplest method now that you have the R134 fittings on, is to use R 12A. It is a Hydro Carbon based refrigeratant that Federal law allows R134 systems to be replaced with. The R-12A is completely compatible with the R-12 seals if you add some of the R12A compressor oil at the time of refilling. The only drawback to using R12A is that it does burn, so if you are very paranoid about fires you may not want to use it, as it will add fuel to any fire if you have a leak.

But the biggest advantage (besides being Ozone safe) is that it is about twice as good as R12 for cooling and about 4 times better than R134 for cooling.

 

OK, still wondering about the evaporator, condensor, dryer & all.

If we pull the compressor & drain it & put it back in, wouldn't the rest of the system components have enough compressor oils to still foul-up the works?

Icemark, you said to drain all the R-12 and R134 (and oils) from the system. Is that a backyard project, or are you saying to have it pumped-out by vacuum at an AC servicing shop?

The compressor oils are in the freon, right? Am I right? I would like to just pull the compressor & drain it & put it back in, but isn't the whole system now all full of crap?

If this is correct, would it not be the time to take it to the AC servicing shop to have them pump-out all of the crap out of the whole system & charge it with R134 or R12A? Seems the whole system needs some kind of flushing.

In case it's not obvious, we're flying blind here. Have no experience in AC servicing at all. Got more than basic knowledge & experience in engines & stuff. AC systems & trannies come to mind as to total lack of experience though...

edit: Oh yeah, the high gage readings on the low pressure port had me thinking that the compressor wasn't working anyhow. Any merit to that?

BTW: Thanks all for your involvement here. Muchly appreciated!!!

 

Hmmm...

 

my solution is to drive at night

 

bump

 

Okay, what I use is a product called "freeze 12". Its a direct drop in replacement for R12, runs at a lower operating pressure, and is fully compatible with the R12 oils and seals. AND ITS NOT FLAMMIBLE. The R134 is not only incompatible with your system, its advanced pressure curve will blow your coolant lines ASAP.

Unless you added R134 that contained the oil in the can, you didnt add any oil, you just added coolant. What I would do:

Either take the car to an AC tech and have them pull a vacuum on it, or you could try adding freeze 12 to the system.. Only problem with that is, there is Freon, and r134 in that system now, the contamination factor is pretty big.

 

Yeah, oil was in the can...

All this help with what to recharge it with is nice, but still many questions go unanswered.

 

Whats the question?

 

edit: Oh yeah, the high gage readings on the low pressure port had me thinking that the compressor wasn't working anyhow. Any merit to that?

 

If compressor is still envisioned to be very possibly in good condition...

Main Question #2: Will the AC tech - pulling a vacuum - suck all of the bad stuff outta there, or is the system still gonna be full of the bad stuff?

We need this system to be in a condition that is worthy of re-charging with [whatever] first-off. Right now, it isn't and we are trying to find out just how to get it there, first-off...

Will pulling a vacuum put the system in the state of readyness for the subsequent re-charge of "freeze 12" or "R12A" or R134? It doesn't seem at all like a good idea to put the "freeze 12" in at this point.

 

Freeze 12 is the same thing as R12a and is hydrocarbon based, making it flamable

 

So why does all the testing on the product allow it to claim non-flammable?

 

Maybe they have added something to it. Check the contents to see if it is Chlorine, Freon, or Hydrocarbon based.

Chlorine is illegal, and Freon has its R problems.

 

Here, read it for your self....http://www.freeze12.com/

 

Ahhh I found it, Freeze 12 is really R-142B and a Class 2 referigerant (which means in the USA you technically need a trained technican to purchase and install). In addition, it appears (based on the EPA data) not to cool as well as R 12, but still better than R 134.

 

and since I have a licence.. I can purchase and install it.

 

What he said.

 

Yeah. What I said.



('Sceeeuze me...)

 

Permit me to re-phrase Q1...

Does high pressure on low pressure port = bad compressor?