# a/c problem, noise



## Solidox2k (Jan 21, 2004)

i recently just got my a/c working (yay  ). i replaced the low side line and new O-rings...had a shop charge it for me (r134a). after i got it home, noticed a 'clacking' noise, and added some refrig. oil; that took care of that. but....

after i turned off the a/c, i had a loud gurgling/buzzing/grinding type noise. i searched last night and tried a few things. i ended up spraying some lubing spray onto the clutch on the a/c compressor and that took care of it. anyway, no noise after spraying it, but it worries me. it only made the noise when the a/c was off, and when the a/c was on, the noise would completley go away.

is this a sign of the clutch going out??? 

i'm about to leave to austin pretty soon and have a considerable load in the car. so i'm hoping someone can help; certainly dont want something to go wrong on that long hr trip.


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## Solidox2k (Jan 21, 2004)

well no one's replied. 

yes i _have_ searched. nobody's problem sounded like mine. so i didn't quite find the answer i was looking for.

it's been a while since i sprayed the lube oil between the clutch and the pulley. the noise came back again. i know only the basics of A/C, but nothing about compressor construction. so i dunno if this is because of the bearings or something else. 

i looked at it while the engine was running and the A/C clutch (A/C and blower OFF) seems to be 'slipping'. even though its supposed to be off and not turn w/pulley, it sorta 'catches' for a split second at random intervals, and will slowly move, sometimes 1/8 revolution and sometimes it will slowly do full turns....then stop...then move again slowly, then stop, etc.... each time it moves it makes that same noise. something is giving friction to it, but i have no idea what. could it be catching on the pulley face???

if so, will lubing it every now and then be enough???.....could it make a 600mile trip in this condition?


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## HATEnFATE (Dec 24, 2002)

Sounds like you might have a problem with the compressor/clutch. From what I know the Clutch is not servicable apart from the compressor. 

I don't know the exact condition that yours is in but I would THINK you would be ok for 600 miles. I'd hate to have you drive that far and have issues though too.


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## Solidox2k (Jan 21, 2004)

thanx for the reply. i remember in a few posts i think (while R&Ding for quite some time before posting this thread) that the clutch was servicable......

too late now though  seems it's now making a distinct scraping noise...turning into a horrible squeeling one at high rpms; a/c on or off, plus it's slipping.... so....at least i got to enjoy a/c for a week. gonna take it to a shop tomorrow, wont be easy with all my stuff still loaded in the car; its riding low (plus the 32" TV i somehow fit in there)and there's alot of steep lot entrances and hills here. im hoping its something that can be serviced w/o a discharge.


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## tom434 (Feb 24, 2005)

the clutch is easy to replace.The comp may be on its way out you will know because it will lockup and throw the belt like mine did or not come in at all.If its low on charge it will cycle in and out.From my own experience the comp in my aerostar made noise off and on before going out.I got one off ebay {used for 20 bucks} and its worked for 2 years.I've seen them for your car remaufactured on ebay for 69.95 

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7979285276


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## Solidox2k (Jan 21, 2004)

:crazy: of course, Ebay! didnt even think about it. cool, thanx for the link. good thing since the shops i called suggested a compressor replacement, cause they dont do compressor work, or say its too hard to find clutch sets for the car. they were just normal shops, no specialized a/c shops.

looks like i'll have to replace the compressor anyway. guess i'll just take the belt off it for the trip. feels like such a waste for the money getting it charged and working


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## tom434 (Feb 24, 2005)

Solidox2k said:


> :crazy: of course, Ebay! didnt even think about it. cool, thanx for the link. good thing since the shops i called suggested a compressor replacement, cause they dont do compressor work, or say its too hard to find clutch sets for the car. they were just normal shops, no specialized a/c shops.
> 
> looks like i'll have to replace the compressor anyway. guess i'll just take the belt off it for the trip. feels like such a waste for the money getting it charged and working


 And for some reason the comp with clutch already mounted is cheaper than the comp alone.Some are tough the one on my aerostar was on the bottom of the engine right above the frame i had to remove the alt and its mounting bracket to get to it but i've been doing this stuff for 20 plus years.I did the same as far as charging had the van charged and 2 weeks later the comp locked.Most gen shops don't have a clue and the specialty shops charge a premium.


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## PeaNutB13 (Apr 14, 2004)

By chance did you change the dryer since you had the system open? and did the shop flush the old ISH out before they charged it? It sounds like something is cloged with sludge to me. and the oil is not getting to the compressor like it should be. 

Just my .02


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## Solidox2k (Jan 21, 2004)

PeaNutB13 said:


> By chance did you change the dryer since you had the system open? and did the shop flush the old ISH out before they charged it? It sounds like something is cloged with sludge to me. and the oil is not getting to the compressor like it should be.
> 
> Just my .02


ya know, i meant to, but somehow it slipped my mind. the dryer really should've been changed....that car had been w/o a charge for more than a year and a half. i tried charging it a while back, but got really abnormal pressures, and it wouldnt take. later i replaced the low side line, then had it recharged last fri. i didnt take the car, someone else did, so i dont know much of anything they did. i do know something of a 'valve core' was replaced. funny, it needed a lil' oil after i got it back. put 2oz in.


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## Twiz (Aug 24, 2004)

If your compressor squeals then it could be:

1) A/C belt out of adjustment (you need to tension it)

2) You overcharged the system with either too much oil or freon. The compressor will cycle repeatedly but won't engage. Rev the engine to 3000 - 4000 rpm and let it drop... if the radiator fans stop and start again then your system is overcharged.


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## Solidox2k (Jan 21, 2004)

Twiz said:


> If your compressor squeals then it could be:
> 
> 1) A/C belt out of adjustment (you need to tension it)
> 
> 2) You overcharged the system with either too much oil or freon. The compressor will cycle repeatedly but won't engage. Rev the engine to 3000 - 4000 rpm and let it drop... if the radiator fans stop and start again then your system is overcharged.


well i know the belt is tight enough. why would revving like that tell me if it's overcharged??? i'll check anyway, but im sure its the clutch. i got a set of pressure gauges too, i'll check with those as well.


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## Solidox2k (Jan 21, 2004)

*I wanna cry now....*

well, i got to austin fine, except the compressor died on me. i only used it once when i hit the humidity, it was cool, then suddenly just got warm.

i took it to a mechanic here my sister trusts real well (pretty cool, i think i can trust him). he did some overall checks and all he can figure is the compress isn't compressing (even though it engages, etc.).

the guages showed NO change when a/c was turned on, and low side was really high (like near 100), actually equalized with with the high side. aside from a few minor things that was the main thing that convinced him. we found black gunk (oil?) throughout the system. he says i need a new compressor (np, wanted a new one anyway) BUT now that that black stuff is in the lines, we're gonna have to do a flush, PLUS replace the expansion valve and the reciever dryer. he told me an estimated $350 for labor minus the parts. ouch. not to mention the cooling unit will have to be flushed prior to the expansion valve being replaced/installed.

my question now is: 
1)$350 to install all that and the flushing a good price?

2) how is 'flushing' the a/c components done? or rather is this something i can do myself (so i can cut the price down by flushing the cooling unit and replacing the valve myself)?

........and now the rear main seal is leaking i think (yay). im having fun, lol. *sigh*


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## steven (Jun 13, 2005)

I am having the same work done on my daughters 92 Sentra. That is a good quote. I am going to do most of the work myself, to keep the cost down. I fouond a rebuilt compressor on Ebay for approx $130. That is from a well known national rebuild company. 

The black death is typical. flushing out the system is the cure, but it has to be well done. It does not take much to plug an expansion valve.

I am looking for a good vacuum pump right now. I am hoping I can borrow one. I have seen the syphon type on Ebay, but I am know sure if 28" of vacuum is enough. I have read that you need 30" or better to get all the moisture out. One person suggested using nitrogen to do an initial purge, 

In one of your early posts you said that you had replaced some O-rings. Where did you find them ? Did you get the buta-n(black) or Ryton ?


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## Solidox2k (Jan 21, 2004)

steven said:


> I am having the same work done on my daughters 92 Sentra. That is a good quote. I am going to do most of the work myself, to keep the cost down. I fouond a rebuilt compressor on Ebay for approx $130. That is from a well known national rebuild company.
> 
> The black death is typical. flushing out the system is the cure, but it has to be well done. It does not take much to plug an expansion valve.
> 
> ...


i asked a couple of mechanics (including this current one) about the vacuum. they all said pretty much the same thing. 30" of vacuum is preferred, but usually 26"+ will be good enough. i guess it depends on your vacuum, and just how good you wanna be on expelling moisture.

the last shop that had charged the a/c when it was working replaced the O-rings, so i dont know what kind they were.

yea, seem to be a few posts <$100 on ebay. they are mostly for 92's but im a 93', only a year difference and in the 91-94 range so im hoping it will fit fine.


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## Solidox2k (Jan 21, 2004)

Steven, what exactly was wrong with your AC system that was going to cost you $800? Cause I just realized that the parts added will cost me almost $700. Wondering if you had to do something like flushing, and how it is done....


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## Catman (May 21, 2004)

I have a rebuilt compressor I got for my 93 Sentra online that basically sat on my car for 1 1/2 years discharged. I took it to a one man shop, replace dryer twice, condensor, expansion valve, but system was not clean and killed the first rebuilt compressor. When the second one was installed, it was run for 15 minutes, and pressure readings were off. System was discharged. I just removed it recently, and the compressor oil looked new. I spent $850 dollars on parts and repairs. You can have the compressor for shipping. I have no way of testing it, but did buy it from a company that seemed reputable. PM if you are interested. I have the numbers off the original compressor to see if it will fit.


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## steven (Jun 13, 2005)

The expansion valve clogged, excess back pressure caused the compressor seals to blow. 

I plan on removing the old compressor, drier and expansion valve, then flushing the system. I have had various suggestions of paint thinner, mineral spirits & alcohol to use as a flushing agent. I have no idea which is better. I figured to start with the mineral spirits, let them soak in and soften the black goo, then finish with something a little more aggressive. I had planned to pour the liquid in with a small funnel, and use air pressure to push it through.

I have had no luck finding a vacuum pump to borrow, so I might end up with one of the syphon type pumps off of ebay.


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