E70 sprayed out all Freon

[Serf27]

Well I’ll double check the gauges hooked up agai. Possible they weren’t at 0 when I got them, which would be odd.
I can see this part spinning on the compressor.

[RL18]

Let us know the results!

Hopefully you can get that compressor running again.

How many oz do you think you've added so far?

[Blackbeard 1706]

ok, comparing the difference between gauge temperature and actual line temperature is going to give you something referred to as "superheat" or "subcooling" values.
Absolutely useless in automotive systems, as cars use a compressor that is belt driven and subject to engine rpm, a/c compressor spinning 1,000 rpm in the driveway and 4,000 rpm on the freeway would lose/gain superheat with every stomp of your right foot, so those values are not used, do not apply here.

I stand that quite likely your compressor isn't even spinning, if it is, it's certainly not pumping.

the real pita is that bmw used a variable temp sensor in place of the conventional low pressure switch, there's nothing to jumper to bring the ac compressor on manually.
I would try to connect a primative test light into the compressor clutch to verify it's getting power, or get a skinny volunteer under the car to see that clutch actually spin.

[Blackbeard 1706]

I'm seriously wondering if the car's potentiometer style pressure switch isn't allowing the compressor clutch to energize do to refrigerant pressure values failing to match bmw's ideal algorithm due to the charge not being close enough.
or, if a coding tool like mine could plug in, put the compressor into a test mode to override the system and manually force it on.

more on that later when my wife returns with her car.....

[Serf27]

I’ve added almost an entire 12oz can so far.
I hooked up with the gauges today. Pressures were a lot lower. Maybe the gauge was not at 0 yesterday for whatever reason.
After I purged the lines, I had 28psi on the low and 25 on the high.

Important to note, the clutch was spinning prior to purging the lines. Once I did that, the clutch stopped spinning. Did it stop because the loss of pressure? The clutch is the part I circled in the photo I posted earlier right? I can see that part spin from the top. But now it’s not spinning.

I didn’t look too carefully down at the compressor but looks like it will be difficult to get a test light on there.

Do you have a special AC coding device?
I have a bmw coding tablet but it doesn’t show any compressor errors.

Next step would be to add more Freon now that the gauges are working properly?

I taking it on a trip the 12th of next month.

[Blackbeard 1706]

more gas..
with the compressor off, not running, expect both gauges to read maybe 100 psi, maybe more, depends on ambient load, could be anything, but still high and the same, both gauges...
now with it running, you need the blue one 30-35 psi, you can see when that needle hits 27 psi, it's evaporating at 32°, that's your minimum, gotta keep it above freezing, target is about 30-35 psi.
red side will show head pressure, also the temp that the gas is condensing at, but the only thing important is that it is reading significantly higher than the low side..like 80- 100 psi higher, way higher.

[Serf27]

The blue one was nearly at 30 psi with the compressor shut off and hot air blowing out of the vents.
How much psi could a 12 oz can add?
I’m going to buy some Freon right now and put it in and report back.

[Serf27]

No dice.
Tried to add more Freon and then the pressures equalized and everything just sat there.
Low side got up to 110 psi and the high side up to 100 psi.
The front part of the compressor turns on and spins. It turns on and off if I press the AC button inside the car. I didn’t wait there to see if it would cycle on and off alone.

I tried to bang on the compressor, I couldn’t really access the sides though. Just the top and another area of the top. Hard enough to leave marks on the compressor housing but nothing changed.

So is the compressor bad? Is that the next step, to replace that?

[Blackbeard 1706]

if the compressor clutch engages, and the blue, low side gauge pressure doesn't drop, it's not pumping and the compressor or it's clutch is bad.
generally safest just to buy both parts as an assembly.
if the pump is cycling on and off on its own, the charge is still low enough that its pumping down once it engages to trip off on the low pressure switch.

[Serf27]

Originally Posted by Blackbeard 1706

if the compressor clutch engages, and the blue, low side gauge pressure doesn't drop, it's not pumping and the compressor or it's clutch is bad.
generally safest just to buy both parts as an assembly.
if the pump is cycling on and off on its own, the charge is still low enough that its pumping down once it engages to trip off on the low pressure switch.

I was doing this alone and no camera on the gauges and I also didn’t wait long enough to see if the compressor cycled on its own and dropped pressure.
I’ll try it tomorrow morning.
I’ll have someone turn the AC on and off and also wait a while to see if the compressor cycles.
How often should it cycle? It will be about 95° when I do this.

Once I do this, (cycle compressor on and off) and pressure doesn’t change, it’s time to change the compressor?
Thanks.

[Blackbeard 1706]

static pressure (not engaged) if full, should be high. when the pump runs and starts pumping, the blue will drop and the red will rise. when not running the two even out somewhere in the middle. Low pressure switch cut out .is likely around 20-25ish psi blue gauge.
cut in pressure could be much higher.
compressor will not cycle on and off, just stay on as long as blue gauge pressure can stay above the cut out switch.

[Serf27]

Thank you.
I put the gauges near the windshield so I could watch them and they do not even flinch when I turn the ac/clutch on.
I hit the compressor a few more times.
A couple of times it started to make a grinding type noise and then it would stop.
I’m currently looking at this compressor
https://www.ebay.com/itm/A-C-Compres...-127632-2357-0

[Serf27]

There’s a lot of options for it.
Some mention 8 groove pulley and one mentions adaptive drive, which I have.

[Blackbeard 1706]

owch, seems pricy. Last summer I replaced compressors in our land cruiser and F250, combined both were less than that one, but I guess it is what it is.
look for one that includes compressor oil, they come shipped dry and will need 3 or 4 oz usually. Often is included, that one doesn't seem to have it.
That plug near the liquid line port is the over pressure relief pop off valve.

[Serf27]

The prices are up there but not as high as I was thinking. ($400+)

I called partsgeek and they gave me 2 options.

Option 1 is the compressor alone.
Option 2 is the compressor and oil with O rings and expansion valve.
Difference of around $40.

2 questions for you guys.
Do I need the expansion valve and the other stuff? If not, I’m sure I can buy the oil at an auto parts store for less than $40.
And would it be that much added work to replace the expansion valve? If it is out of the way, I probably won’t install it and would be pointless to buy the kit combined.

Here are the links to the compressors.

https://www.partsgeek.com/ss/?i=1&ssq=96160-06084616

https://www.partsgeek.com/ss/?i=1&ssq=96160-05905143

[Serf27]

Installed the new compressor today.
AC seems like it’s colder than before!
My pump could only pull 20in of vacuum but it held the vacuum after I let it sit.
When I disconnected the red high side line from the car, it still read a lot of pressure in it. I released it and Freon came out of the red line(not connected to the car at this point) not sure why.
But it’s working again.

Thanks to both of you for all the help.

[jpcallan]

Originally Posted by Sophisticated Redneck

Most likely will be a crack in one of the rubber lines that will be hard to spot. I would grab a manifold set and vacuum pump off Amazon if you don't have one already, hook up the manifold and verify pressures to see if it's on the low side or high side (most likely high and both pressures will probably be zero). If it is at zero then hook manifold to 100psi air compressor and let in through high side valve. You should be able to hear where leak is coming from.

Using compressed air is very unwise advice, potentially destructive.

The PAG oil used in auto A-C system is hygroscopic (water loving), so pressurizing the system with air and its humidity would turn the PAG oil into acidic oil and poison the system's dryer desiccant as well. Only dry nitrogen (or argon, if you have money to burn) is suitable to pressurize the A-C system for leak testing.

You may have noted A-C systems all have a "receiver-dryer" or "accumulator-dryer". That's where the desiccant can be found; it's there to scavenge the last tiny traces of moisture from the refrigerant stream.

[jpcallan]

Originally Posted by Serf27

I was towing a van with my e70 35i yesterday. Everything was fine...

I now realize the smoke from the engine bay yesterday must have been the AC Freon. Visually everything looks fine from the top. no torn ac lines.

Has anyone seen or heard of this?

Yes - I have seen your problem, sadly more than once.

Check your radiator and condenser for bugs and greasy dirt plugging the fins.

When the A-C system can't get rid of the heat it collects from inside the cabin it results in the refrigerant pressure rising to the point where the compressor clutch slips and smokes, or depending on the system design, either: 1) A safety relief valve opens and vents off the extreme refrigerant pressure; 2) On older cars, a fuse plug melts and blows off the refrigerant charge.

I saw in later posts you replaced the compressor. You may not yet have gotten to the root cause - your A-C system can't get rid of the heat it's collected. The #1 cause is a dirty or fouled condenser/radiator/transmission-cooler. #2 cause is the electric fan(s) failed or a fan relay is preventing the fan(s) from operating. I've had this failure most recently in an Audi when the fan cycling thermostatic switch failed.

This past month I had my buddy Dave's 2008 X5 4.8l over at my house (Dave is in England) for a rear brake job and to replace three fractured engine bulkheads. He mentioned the A-C just wasn't working as well as it ought. My thinking was the A-C was inhaling really hot air from the engine compartment because of the collapsed engine bay bulkhead. After replacing the bulkhead parts, test driving the car, the A-C was somewhat cool on the driver side vents, but warm on the passenger side vents. With charging manifold attached, the high-side refrigerant pressure was up over 400 PSI - way to high, and the low-side was down fluttering around 10 PSI - way low (30-35 is about right for R-134a). Adding 10.5 ounces of R-134a had all vents nice and cold again.

Dave's X5 lost about half its refrigerant charge, and the bottom half of the radiator was completely blocked with greasy dirt and bugs. About half the condenser and transmission cooler were also fouled with greasy dirt, just not as badly. Strangely, the top third of the radiator was mostly clean. A trip to the DIY carwash for a low-pressure rise after a thorough treatment with professional HVACR condenser cleaner had everything mostly clean, although it did require two treatments.

Oregon had all-time record heat this past summer. My working theory is running with a fouled condenser drove the system pressure high and the high heat made it worse. I think the A-C system's o-rings and gasket joints had been leaking slowly because of the high refrigerant operating pressure, leading to the refrigerant loss.

After cleaning, shine a flashlight from behind your radiator while looking through the front grille. Paint the whole radiator with light. Plenty of light should shine through. If not, more bugs and dirt may be trapped between the trans-cooler and the condenser, and/or between the condenser and the radiator. It may be necessary to loosen the condenser and blow out the fouling between with compressed air, then wash again to get it really clean and free flowing.

Best luck.

[Serf27]

It did not fail while towing.
It failed about 2 hours later. Maybe the heat generated while towing did cause some damage to the compressor.

In an earlier post I mentioned the compressed was seized I believed. Hitting it with a long pry bar would free it up for a quick second.

The AC is almost too cold now! It’s been working great beer since I replaced the condenser. I will still take a look at the radiator and condenser for debris.

Here’s a photo of the old compressor.
That center part would not spin In a true circle. It spun in any direction.

[jpcallan]

Originally Posted by Serf27

It did not fail while towing...

The AC is almost too cold now! It’s been working great beer since I replaced the condenser. I will still take a look at the radiator and condenser for debris.

Here’s a photo of the old compressor.
That center part would not spin In a true circle. It spun in any direction.

Glad to hear it's way cold inside!

I can see melted rubber from the magnetic clutch slipping - either the pressure got so high the clutch began to slip, or the compressor's internals seized up. My guess is ram air kept enough air moving through the condenser while towing, but when you stopped so did the ram air, letting it overheat.

On Denso compressors like yours one can replace the clutch, usually with the compressor still mounted to the engine, like on my wife's 1996 Jeep Grand Cherokee. Not that easy on an X5, sorry to say. Sometimes when the clutch slips or won't engage, there is a shim pack behind the rubber plate. Removing a shim or two will tighten up the clearance between the metal drive plate and rubber clutch. Just like that, the compressor come back to life, but you have to catch it before is self-destructs by slipping.

I didn't realize you changed both the compressor and the condenser. BMW uses what are called micro-channel condensers and radiators built in the same style. These both have fins that plug easily, bend and fold over if sprayed with a pressure washer, and are tough to unplug.

I'll probably pull the radiator and condenser from my buddy Dave's X5 this winter, when he is next overseas, and steam clean them both from the back side forward. After that, several hours with a fine pick straightening the folded over fins. The lower third of the radiator really collects garbage on his E70. Using the light test, even after cleaning, little light shines through from back to front in the radiator lower third.

Again, glad to hear things are working well.

[Serf27]

Actually, I didn’t replace the condenser. I typed that by accident. I only replaced the compressor.

I can’t access the front of the compressor while installed, and 1 bolt on the compressor makes removing it a hassle.
The new compressor assembly was ~$240, so not bad.

I would suspect the upper half of the condenser collects the most debris because of the grills.