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Discussion Starter #1
My compressor is falling apart. The pulley took a hit from the tensioner when the belt was thrown a couple times last year. I have the updated bracket installed now but it's too late for the compressor. It groans and grinds whenever I run it and it's been getting steadily worse over the last couple months. Most likely damaged bearings.

Anyway... I was hoping someone might be willing to throw a few tips my way on replacing the compressor. My bro-in-law is a master HVAC technician so he has access to the equipment for recovery, vacuum and leak test as well as a source for refrigerant (134a). I do have a new receiver dryer too.

What I need to know is any tricks or precautions for the mechanical removal and installation of the compressor and the dryer. I did the installation of the updated compressor bracket so I do know how to get that far.

Most importantly, does the compressor need any prep? I've been told by a couple of people that compressors sometimes need to have oil added to them. If that's the case here, what kind, how much and where does it go? An estimate on how much refrigerant I'll need would be great too.

Thank you.
 

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How do you know the compressor is bad? From what I read, all of our compressors moan and groan but maybe not grind. Mine has been moaning and groaning since I bought the car 8 months ago, been doing it all summer in 100+ degree heat on startup, still works great.
 

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I'll try to make sense out of this------ They say that a A/C service center machine will pull out all the refrigerant and oil as well as separate the 2 components. They say to take note of amount of oil removed (so as to add that same amount when recharging takes place). But that bothers me. My thinking, is if the system had lost *any* amount of refrigerant and/or oil, you wouldn't know the exact amount to add based on the recovered amount. It says new compressors come from the factory serviced with some oil. The say to rotate the compressor pulley to aid in removal of the oil within it. The drawing shows the oil being removed from and added to the smaller of the 2 ports on the compressor. But they tell you to pour it out into a measurement container (to see how much they had added, then put it back in). If *no* oil came in the new compressor, they say to add 2 ounces to it, then >>>> Rotate the compressor pulley several rotations to lubricate all the things in it, then mount it in the car. Using new washers (*without* adding any oil/lubricant to them), reattach the suction/discharge pipes an torque to 16 lb ft. Then reconnect the electrical connector.
They just say (after getting all the necessary things out of the way), to remove the upper radiator support brackets, and tilt the radiator and condenser towards the engine as necessary to gain access to the dryer located vertically on the passenger side of the condenser. When evacuating and recharging, add oil quantity as shown below, minus what ever amount was put back into the compressor.

Use PAG oil---- Total system PAG oil capacity is 3.3 to 4.7 ounces. HFC R-134a quantity is 20.5 ounces. If I see errors , I'll correct on a re-read thru
 

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How do you know the compressor is bad? From what I read, all of our compressors moan and groan but maybe not grind. Mine has been moaning and groaning since I bought the car 8 months ago, been doing it all summer in 100+ degree heat on startup, still works great.
The noise is pretty loud and irregular. At first, it was only when the compressor was running and at elevated RPM. Gradually, it got louder and was doing it at idle. Over the last several weeks, it started doing it when the compressor is off. All of this began within a couple months after the last belt throw. It's clear that the pulley was hit, and hit HARD because there's a 1.5" chip along the inner and outer edges in one spot. I confirmed that it's A/C related by taking off the belt and running the engine at varying RPM. No belt, no noise. The tensioner is new because it came with the updated bracket. The idler pulley on the bracket and the tensioner pulley feel fine. The compressor has visible damage and it's the only thing left.

You're the first person I've heard say that a groaning/moaning compressor is normal. Could just be a matter of personal opinion or interpretation, but what I'm hearing is definitely not normal.

From the engine compartment:
http://www.mediafire.com/download/ci...se_outside.mp3

From the cabin:
http://www.mediafire.com/download/3q...ise_inside.mp3

It's about halfway through the soundbite taken from the engine compartment. Sounds kinda like gears slipping.
 

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Yep that thing is toast lol mine is definitely different and only does it when on initial start up of the A/C then goes away. Out of curiosity how many miles do you have on the car? I'm at 103k right now.
 

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Discussion Starter #6
I'll try to make sense out of this------ They say that a A/C service center machine will pull out all the refrigerant and oil as well as separate the 2 components. They say to take note of amount of oil removed (so as to add that same amount when recharging takes place). But that bothers me. My thinking, is if the system had lost *any* amount of refrigerant and/or oil, you wouldn't know the exact amount to add based on the recovered amount. It says new compressors come from the factory serviced with some oil. The say to rotate the compressor pulley to aid in removal of the oil within it. The drawing shows the oil being removed from and added to the smaller of the 2 ports on the compressor. But they tell you to pour it out into a measurement container (to see how much they had added, then put it back in). If *no* oil came in the new compressor, they say to add 2 ounces to it, then >>>> Rotate the compressor pulley several rotations to lubricate all the things in it, then mount it in the car. Using new washers (*without* adding any oil/lubricant to them), reattach the suction/discharge pipes an torque to 16 lb ft. Then reconnect the electrical connector.
They just say (after getting all the necessary things out of the way), to remove the upper radiator support brackets, and tilt the radiator and condenser towards the engine as necessary to gain access to the dryer located vertically on the passenger side of the condenser. When evacuating and recharging, add oil quantity as shown below, minus what ever amount was put back into the compressor.

Use PAG oil---- Total system PAG oil capacity is 3.3 to 4.7 ounces. HFC R-134a quantity is 20.5 ounces. If I see errors , I'll correct on a re-read thru
Thanks GOPHERIT... This is great info!

So, if the oil cap is 3.3 to 4.7 oz, that's a fairly wide tolerance so should I just go with the middle ground at around 4 oz?

Also, which "new" washers are you referring to? I have a new OEM compressor and receiver drier. I didn't buy any seals or washers. Should I and if so, what should I get?
 

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Discussion Starter #7
Yep that thing is toast lol mine is definitely different and only does it when on initial start up of the A/C then goes away. Out of curiosity how many miles do you have on the car? I'm at 103k right now.
76K last I looked. I bought it a little over two years ago with 46K on it.
 

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Discussion Starter #8
The tragedy for me is that other than the ridiculous noise, the system seems to be functioning great which only confirms that it's definitely not due to lack of refrigerant. If it wasn't for that damn belt popping off, I probably could have gotten another 50k out of that compressor.

I know some might say that if it works, ignore the noise and leave it alone but I can't do that. I can't afford to have this thing crap out on the highway during a winter rain. That happened to me in my old car where I damn near ran off the road when my windows completely fogged up in a matter of seconds. I had to pull over to the shoulder and crawl to the next exit and park it until the weather cleared.
 

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I knew I would miss something here. There is a bolt that secures the pad that supports the suction an discharge pipes to the compressor. The 2 pipes extend into the compressor a touch, and each has a one time use throw away seal around them. Those are the 2 seals that have to be replaced (unless you think they will still seal up the system correctly if left in place). 4 ounces of oil sounds like a can't miss quantity. If 2 ounces were known to be in the compressor at installation, would evacuating the system for the re-charge procedure, try to draw that 2 ounces back out or leave it where it currently is ? Course the HVAC tech would know for sure. They don't show or talk about any seal for the dryer. Must be self sealing upon installation.
 

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Discussion Starter #11
I knew I would miss something here. There is a bolt that secures the pad that supports the suction an discharge pipes to the compressor. The 2 pipes extend into the compressor a touch, and each has a one time use throw away seal around them. Those are the 2 seals that have to be replaced (unless you think they will still seal up the system correctly if left in place). 4 ounces of oil sounds like a can't miss quantity. If 2 ounces were known to be in the compressor at installation, would evacuating the system for the re-charge procedure, try to draw that 2 ounces back out or leave it where it currently is ? Course the HVAC tech would know for sure. They don't show or talk about any seal for the dryer. Must be self sealing upon installation.
I saw at least one o-ring on the drier that I bought so they might be all that's needed.
 

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Discussion Starter #12
GOPHERIT...

Would you happen to have the part number(s) for those two seals? What I found was a transducer o-ring, GM part# 92148455.
 

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I can't find any info on those 2 seals/o'rings. Since they tell you to replace them each time that pipe connection is opened up, you know they are available. It looks like you'll have to visit a GM parts counter. They must have the required IPC charts and P/N's for those seals/o'rings.
 

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AutoZone sells a 38 piece Santech kit for only $6. I think I'll go with that and hope for the best.

Anything else I should get? I saw a video that recommended replacing the "orifice tube" and flushing the system. Are either of those really necessary?

My brother-in-law says that he will need some kind of hose/adapter to hook up the 12oz R-134a cans to the car system. Anyone know what he's talking about?
 

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This car uses a Thermal Expansion Valve at the firewall to control the refrigerant flow into the evaporator instead of an orifice tube setup (forget about it). I'm pretty sure that the system would only require a flushing procedure *IF* the A/C cooling system had a total failure an debris was suspected to be roaming around thru the tubing and compressor. I thought that the machine your brother in law has access to, is a do it all machine. What am I not seeing here ? If it can do all those things you talk about, it surely must be able to recharge the refrigerant and oil as required.
 

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This car uses a Thermal Expansion Valve at the firewall to control the refrigerant flow into the evaporator instead of an orifice tube setup (forget about it). I'm pretty sure that the system would only require a flushing procedure *IF* the A/C cooling system had a total failure an debris was suspected to be roaming around thru the tubing and compressor. I thought that the machine your brother in law has access to, is a do it all machine. What am I not seeing here ? If it can do all those things you talk about, it surely must be able to recharge the refrigerant and oil as required.
I really don't know what he has, just that I asked him a while back if he was sure that he could do it being an auto system and not a dwelling. He said that he had recovery and vacuum equipment, but might need an adapter to hook it up. Whether he had what was needed to recharge the system was never really clear. Today I bought two 12oz cans of R-134a and sent him a pic of the top the cans asking if he could hook up to them. He said that he would need "the adapter usually sold separately".
 

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Well, if you have to refill using those cans, you'll probably need to get one of those R134 recharge hose kits. They come with the low pressure side quick release adapter, hose, the thread-on shutoff valve, and some even include a pressure gauge, to see what kind of pressure the system is reading while the A/C is running.
 

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Discussion Starter #18
Well, if you have to refill using those cans, you'll probably need to get one of those R134 recharge hose kits. They come with the low pressure side quick release adapter, hose, the thread-on shutoff valve, and some even include a pressure gauge, to see what kind of pressure the system is reading while the A/C is running.
So, I was in the process of draining the PAG from the new compressor when I noticed a wobble in the pulley as I turned it. It was pretty bad. Amazon replaced it but that one has a slight wobble too. Is this a problem?



Here's a video link that shows what I'm seeing.

https://www.mediafire.com/download/pi73y4nc8nr1brx
 

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Discussion Starter #19
Amazon let me exchange the compressor but the pulley on that one wobbles too. Not as bad but it's there.

I took some better videos and uploaded to YouTube. Please take a look and let me know what you think.

Compressor #1


Compressor #2

 

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I would send both of those back and try to get another. No way they should wobble like that.
 
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