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  #46  
Old July 26th, 2020, 14:25
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blu3fan blu3fan is offline
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Re: Meh a/c

Quote:
Originally Posted by Saudade View Post
Sounds like you have no refrigerant left.

I checked on a spare valve I pulled from a junk yard a while back. Both take about 9 1/2 turns to go from "Back seated" (normal use) to "front seated" (isolate compressor). So when you "open the valve" for servicing, turn the stems about 4 turns.

Back Seated



Front Seated



Mid (servicing)


Since it was empty anyways I just opened the hi and lo port of the compressor and put it midway.



Im 99% sure the compressor is dead unless my t/s is wrong.




Step 1. Adjusted both hi and lo ports to the middle.

Step 2. Added 2oz more of oil since some may have leaked out (Connected lo side port to pump. removed hi side schrader and used a hose to suck the oil into the compressor)

Step 3. Pulled Vacuum.
-30hg both sides. let sit for 60mins. no change.

Step 4. sealed hi and lo on gauges. Removed vacuum pump. Purged air from now connected can.

Step 5. Started car set A/C to hi.

step 6. Opened lo side port showed ~30-50psi once I did this.
High side no change to PSI on gauge.

at this point I expected the can to get lighter.
It did not. It got Icy all over and after 10-15mins compressor was Hot

so I question at this stage because the can got covered in ice.. why? was it pulling? just really really slow due to the valve? I ask this because when I pulled oil WOW was it slow...

Just kinda outlining my process and maybe I've missed something? before I spend another $200 on compressor expansion and dryer.
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  #47  
Old July 26th, 2020, 14:26
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Re: Meh a/c

Sorry I missed *bridged a/c relay when can was hooked up. but u probly guessed that**
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  #48  
Old July 26th, 2020, 16:42
Agreen Agreen is offline
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Re: Meh a/c

Stop jumping the clutch relay. If you pull a vacuum on the system, that alone is generally enough to suck at least a half can of refrigerant in. All you should do at that point is turn the AC on and wait for the compressor to cycle on. I've ONLY ever bypass the clutch relay when I suspect a faulty low pressure switch. You have most likely caused damage to the compressor seals from overheating it.

As to why the can is getting cold: It's when a gas goes from a high pressure to a low pressure, it gets cold. If it's doing this slowly, the amount of gas leaving the can might not change much over time. You seem to still be having an issue getting refrigerant in. If you're attempting to charge it into the low side port, you're doing it right.

Now, you might be able to get it in through the high side while the system is still at a vacuum. If you leave the engine off and vacuum it down through the high side, charge as much as you can into the high side, then shut it off when the pressure equalizes, you might (MIGHT) be able to get the system working. That's assuming your compressor isn't toast. That should be enough pressure to activate the low pressure switch, which will allow the compressor to run. Yes, it's going to cycle. A lot. Start the engine and turn on the AC. Start trying to charge the refrigerant to the low side now. It sounds like the valve has gone bad, but it does allow a little refrigerant to leak by, so it's going to take a while to get it in there. Let it suck the can empty and check the pressures. By the way, I wouldn't really trust the low pressure gauge since it has to go through that suspected valve, so you're going to have to base it almost solely off of high side pressure and vent temperature.
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  #49  
Old July 26th, 2020, 18:00
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Re: Meh a/c

Quote:
Originally Posted by Agreen View Post
Stop jumping the clutch relay. If you pull a vacuum on the system, that alone is generally enough to suck at least a half can of refrigerant in. All you should do at that point is turn the AC on and wait for the compressor to cycle on. I've ONLY ever bypass the clutch relay when I suspect a faulty low pressure switch. You have most likely caused damage to the compressor seals from overheating it.

As to why the can is getting cold: It's when a gas goes from a high pressure to a low pressure, it gets cold. If it's doing this slowly, the amount of gas leaving the can might not change much over time. You seem to still be having an issue getting refrigerant in. If you're attempting to charge it into the low side port, you're doing it right.

Now, you might be able to get it in through the high side while the system is still at a vacuum. If you leave the engine off and vacuum it down through the high side, charge as much as you can into the high side, then shut it off when the pressure equalizes, you might (MIGHT) be able to get the system working. That's assuming your compressor isn't toast. That should be enough pressure to activate the low pressure switch, which will allow the compressor to run. Yes, it's going to cycle. A lot. Start the engine and turn on the AC. Start trying to charge the refrigerant to the low side now. It sounds like the valve has gone bad, but it does allow a little refrigerant to leak by, so it's going to take a while to get it in there. Let it suck the can empty and check the pressures. By the way, I wouldn't really trust the low pressure gauge since it has to go through that suspected valve, so you're going to have to base it almost solely off of high side pressure and vent temperature.

Thanks for all the info. I honestly had no idea. Ill give it one more go. if I cannot get it to pull vacuum new compressor/expansion/dryer here i come.
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  #50  
Old August 2nd, 2020, 07:35
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Meh a/c

So. I repeated my steps. This time moving the valve a little while filling.
After 10 mins trying w/o bypassing relay I gave up. Bypassed it. First can took 20mins
2nd 15more.
1/2 the 3rd can 10mins
Slow filling
45 mins of filling later we have pressures pictured and getting 60f out the vents on a 95 degree morning.
Is the compressor burned out? When the guy at the shop filled it high side line had condensation. Mine is cold but not that cold...





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  #51  
Old August 2nd, 2020, 08:52
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Saudade Saudade is offline
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Re: Meh a/c

Well, the pressures look OK for a 95F day. However, your output temp should be cooler. Did you purge the yellow line before you opened the low side valve to charge? You may have still gotten some moisture in there.

One way to deal with the can icing up is to have a bucket of fairly warm water around. Then dip the can in the water. This helps keep the refrigerant as a vapor and can speed up the filling process.

If I were you, I'd leave it for now. If you haven't done so, don't open the manifold valves. You can keep the lines charged so you don't have to purge them later. Check your pressures again in a few days after a few more cycles. If you did open them, no worries, you'll just need to purge them before adding additional refrigerant, if needed.

I keep a small instant read thermometer (the round dial with the pocket clip) in my center panel vent. On a hot summer day in the sun, the whole Jeep is heat soaked (sometimes over 120F). My AC does take a few minutes to blow cold while it removes the heat from the box, vents and backside of the dash (non-existent insulation). Even more time to actually cool off the inside Once done, windows up, control to MAX, I can get about 40F on a 90F day (OK, I do still run R12).
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  #52  
Old August 2nd, 2020, 09:23
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Re: Meh a/c

Quote:
Originally Posted by Saudade View Post
Well, the pressures look OK for a 95F day. However, your output temp should be cooler. Did you purge the yellow line before you opened the low side valve to charge? You may have still gotten some moisture in there.

One way to deal with the can icing up is to have a bucket of fairly warm water around. Then dip the can in the water. This helps keep the refrigerant as a vapor and can speed up the filling process.

If I were you, I'd leave it for now. If you haven't done so, don't open the manifold valves. You can keep the lines charged so you don't have to purge them later. Check your pressures again in a few days after a few more cycles. If you did open them, no worries, you'll just need to purge them before adding additional refrigerant, if needed.

I keep a small instant read thermometer (the round dial with the pocket clip) in my center panel vent. On a hot summer day in the sun, the whole Jeep is heat soaked (sometimes over 120F). My AC does take a few minutes to blow cold while it removes the heat from the box, vents and backside of the dash (non-existent insulation). Even more time to actually cool off the inside Once done, windows up, control to MAX, I can get about 40F on a 90F day (OK, I do still run R12).
I did purge it but Maybe not as much as should have done? idk.

also I cleaned and disassembled the gauges. >< lol

figured it's good enough for now. maybe ill get it drained and re-fill it later in the year. but working eh// is better than not working at all.
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  #53  
Old September 8th, 2020, 22:00
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Re: Meh a/c

Well. I fixed all the leaks. And it leaked out again.
This time I noticed the inside windshield glass has residue on it.
Evap core is gone huh?

Oh boy... I've been dreading doing this job
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  #54  
Old September 12th, 2020, 19:33
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Re: Meh a/c

Okay.
So honestly I'm in no position to be taking on doing my heater core a/c evap until I have space and time to do it.

Worth a shot to put a "Leak stop" stuff. Since compressor is 50/50 on it being okay. or are these a waste of money? I'm reading mixed reviews.

I know the correct way would be to pull the dash and replace the core. but that isn't happening just yet.
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