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Old Jul 31, 2016 | 08:44 PM
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Default Bad AC compressor?

Hi everyone,

my ac pressure on the low side read 80 psi and 80 psi on the high side when AC is off and clutch disengage. Both low side and high side pressure goes up to 120 psi when AC on and the clutch is engaged

Is this compressor bad or port expansion valve?

I know it's low on Freon, but wanted to fix the problem before adding more, or do I need proper amount of pressure for the Compressor to work properly?

Thanks in advance.
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Old Jul 31, 2016 | 09:40 PM
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I've never seen an expansion valve stick open. Your compressor is shot.
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Old Jul 31, 2016 | 09:59 PM
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Originally Posted by Zkyzork
Hi everyone,

my ac pressure on the low side read 80 psi and 80 psi on the high side when AC is off and clutch disengage. Both low side and high side pressure goes up to 120 psi when AC on and the clutch is engaged

Is this compressor bad or port expansion valve?

I know it's low on Freon, but wanted to fix the problem before adding more, or do I need proper amount of pressure for the Compressor to work properly?

Thanks in advance.
yes, have the proper amount put in. Low pressure should be dropping and high side should be rising when the clutch is engaged. You won't really know what you are working with until you are running the right amount of freon in the system

Last edited by russ472; Jul 31, 2016 at 10:00 PM.
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Old Jul 31, 2016 | 10:33 PM
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Originally Posted by russ472
yes, have the proper amount put in. Low pressure should be dropping and high side should be rising when the clutch is engaged. You won't really know what you are working with until you are running the right amount of freon in the system
Okay Thanks,

Seen like the pressure is too high on the low pressure port to where it won't take anymore freon out of the can so I stopped filling it. I might have to filled when compressor is off. I'm not sure how much I put in. I'll weight how much is left in 22 ounce can.

Just to be sure is it 1.63 lbs is what it call for? My tag are all faded out and can't read it.

Another question is that I can't seen to locate low side pressure switch. Is there one somewhere? in the cab?
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Old Aug 1, 2016 | 09:40 AM
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I don't recall ever seeing a low side pressure sensor--only high side. Computer controls the AC compressor

If you have that much in it it's either overfilled or the compressor is just shot. Probably both.
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Old Aug 1, 2016 | 05:32 PM
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Originally Posted by schpenxel
I don't recall ever seeing a low side pressure sensor--only high side. Computer controls the AC compressor

If you have that much in it it's either overfilled or the compressor is just shot. Probably both.
I don't think it's overfill because today I weighed what is left over in a can of 22 oz still got a little over 19 oz of freon left. Vacuum for 1 hour and filled so shouldn't have that much of old freon in the system if any. Look like I only got less than 3 oz in it. When I turn on the AC and the pressure went up on both side to 120 so stopped charging plus it won't take anymore due to high pressure on the low side.

I may try to add some more freon and see what happen at least its less hassle in case it work than replacing the compressor. The pressure should had gone down sitting over night.

What I don't understand is that why the pressure goes up on both side if the compressor is working? I was thinking the expansion valve stuck open but that should it still see different in pressure? if compressor still good? I don't know it's confusing how this thing work.

Thanks for yours input.
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Old Aug 1, 2016 | 05:51 PM
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When you say 22 oz can, are you using something like AC Pro in a can or something else with some type of sealant in it?
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Old Aug 1, 2016 | 06:32 PM
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Originally Posted by jft69z
When you say 22 oz can, are you using something like AC Pro in a can or something else with some type of sealant in it?
Yes a can from Autoparts store called Arctic Freeze with advance sealant and moisture eliminator or something on that line.
Is this wrong freon? or Am I missing something here? Please let me know before I try to fill up some more.

Thanks,

Last edited by Zkyzork; Aug 1, 2016 at 06:32 PM.
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Old Aug 1, 2016 | 07:42 PM
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http://aircondition.com/tech/questio...ith-Gauges-FAQ
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Old Aug 1, 2016 | 08:27 PM
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Thanks for the link HK770. Lots of good information

According to the article and everyone else keep telling me on here, the compressor is done.

Quote from links above:
"If we hook the gauges up and see 80 psi on the low side, and 80 psi on the high side, and the compressor hub is spinning, it's likely that compressor is done."

But to my issue why when the compressor kick on it changes pressure from 80 psi to 120 on both hi and low side if the expansion valve does not stuck open? Is it because compressor stirred up liquid freon into gas, but didn't have ability to compressed? That's only explanation I can think of. hmmmm??

Here I go tearing of the supercharger just to replace the compressor. Maybe taking off the exhaust manifold route would be easier and less craps to take apart.
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Old Aug 1, 2016 | 08:33 PM
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I was thinking the compressor spinning might be heating things up and increasing pressure.. but that's the best guess I've got.

I removed the head unit and was able to get the AC compressor out the front that way.. it's a tight fit and takes some yanking, but it will come out that way
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Old Aug 1, 2016 | 08:35 PM
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Originally Posted by Zkyzork
Yes a can from Autoparts store called Arctic Freeze with advance sealant and moisture eliminator or something on that line.
Is this wrong freon? or Am I missing something here? Please let me know before I try to fill up some more.

Thanks,
Usually putting that stuff in there is like putting glue into the system. A lot of shops won't touch your car if they know that is in there (including me). It can plug up the expensive filters on the A/C machines.

If there is a problem or a leak, fix it the right way or risk spending a ton of money to flush it out and replace a lot of parts before using that stuff. Some here will say that stuff is great, I'm not one of them. Unfortunately, the stores put that stuff right up front and center for everyone to see. Look for virgin R134A if you can, it's usually hidden away on the bottom shelf of Walmart or the auto parts store. I'd hate to see you cause more problems than is already there by introducing that stuff into your system.


"Google AC sealant and orifice tubes" and see what you get.... Here's a sample:

https://traxxas.com/forums/showthrea...ar-s-AC-system

Check out iATN in the A/C section. Any of the other techs or shop owners will say the same thing without question.



HK770 sent you a link I was going to post that's good, here is another that's OK with a good symptom chart:

http://www.instructables.com/id/How-...Automotive-AC/

Another with 4 parts to it, also good:
http://www.agcoauto.com/content/news/p2_articleid/256

Last edited by jft69z; Aug 1, 2016 at 09:01 PM.
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Old Aug 1, 2016 | 10:16 PM
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Originally Posted by jft69z
Usually putting that stuff in there is like putting glue into the system. A lot of shops won't touch your car if they know that is in there (including me). It can plug up the expensive filters on the A/C machines.

If there is a problem or a leak, fix it the right way or risk spending a ton of money to flush it out and replace a lot of parts before using that stuff. Some here will say that stuff is great, I'm not one of them. Unfortunately, the stores put that stuff right up front and center for everyone to see. Look for virgin R134A if you can, it's usually hidden away on the bottom shelf of Walmart or the auto parts store. I'd hate to see you cause more problems than is already there by introducing that stuff into your system.


"Google AC sealant and orifice tubes" and see what you get.... Here's a sample:

https://traxxas.com/forums/showthrea...ar-s-AC-system

Check out iATN in the A/C section. Any of the other techs or shop owners will say the same thing without question.



HK770 sent you a link I was going to post that's good, here is another that's OK with a good symptom chart:

http://www.instructables.com/id/How-...Automotive-AC/

Another with 4 parts to it, also good:
http://www.agcoauto.com/content/news/p2_articleid/256
I wish i could've known that before I put that crap in there. The freon can said 50% cool faster and advance leak prevention ......... whatever else they said on can. shame on me i guess

Should I do a full vacuum again and refilled with the right stuff or just cross fingers and hope it will be okay? If that would help.

I don't think i have any leaks from what I can tell. I vacuum tested to be good. Anyway I just got it working by adding some more freon. I don't know if it fix itself or fooling with me, but hey it's blowing cold air for now. I end up 9 oz left in the 22 oz can =~ 13 oz in the system. It may need more but i'm not sure exactly how much to put in since my tags all faded out and can't read the freon capacity info. I keep it there for now unless someone here tell me how much of freon is needed or until stop blowing cold air.

on idle pressure read:
high ~250 psi
low ~ 40 psi

at 1500 rpm:
high ~290 psi
low side went down to ~30 psi

~95 to 100 degree ambient, a little low according to the chart but will do for now.

russ474 was right, to you

yes, have the proper amount put in. Low pressure should be dropping and high side should be rising when the clutch is engaged. You won't really know what you are working with until you are running the right amount of freon in the system
If someone would let me know how many pound of freon I needed would be great.

Thanks everyone for the help...
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Old Aug 1, 2016 | 10:25 PM
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Originally Posted by Zkyzork
If someone would let me know how many pound of freon I needed would be great.

Thanks everyone for the help...
Your car takes 1.1 lbs of R134A
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Old Aug 1, 2016 | 10:48 PM
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Originally Posted by jft69z
Your car takes 1.1 lbs of R134A
Thank you,

so i'm a few oz short.

why didn't I run into this "not to use" sealant freon can's deal. Been searching up and down all over the forum and google the web the whole weeks. And why they are allow to sell them everywhere if it's that bad. Ruins the whole ac system. and The autoparts guys didn't do too much help either.

Well it is what it is... have to deal with it. whose to blame but myself.

Thank you again everyone
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Old Aug 2, 2016 | 06:59 AM
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Originally Posted by Zkyzork
Thank you,

so i'm a few oz short.

why didn't I run into this "not to use" sealant freon can's deal. Been searching up and down all over the forum and google the web the whole weeks. And why they are allow to sell them everywhere if it's that bad. Ruins the whole ac system. and The autoparts guys didn't do too much help either.

Well it is what it is... have to deal with it. whose to blame but myself.

Thank you again everyone
One of the pictures in the link provided earlier said it all when I saw it:




The parts guys are just trying to sell product. There's a reason you won't find 30 lb tanks of refrigerant with sealer in them, the professionals don't use it.

On the bright side, maybe that sealer could have 'fixed' a leaking expansion valve which was a symptom of high suction side pressure & low discharge side pressures. Hopefully it will continue to work for you and make cold air.

If you want to further your education, google: A/C compressor black death.....that's another nightmare.
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