A/C cluch or compressor

[zigzag]

as of now the clutch connector is unhooked.. so its leading me to believe either the clutch or compressor is bad... so how do i tell the difference as to whether the clutch or the compressor is bad so i don't have to buy the entire assembly to be sure?

[Century7667]

Generally speaking. compressor clutches make noise when engaged if they are bad. I'm sure some could make noise when not engaged however.

Ken T.

[turbokinetic]

The clutch (pulley) contains a ball bearing that spins whenever the belt is turning. If the clutch pulley is bad; the noise will happen whenever the engine runs.

The compressor only runs when the A/C is on. If the noise happens whenever the A/C is on (may cycle off/on) then the compressor its self is bad.

Hope this helps!
David

[Prospeeder]

Yea, Compressor off and noise = Pully bearing
Compressor noise only when A/C on = Compressors bad

The clutches typicly either slip or dont work period

[SilentWing]

Speaking of compressors (sorry for hijacking) I'm probably going to end up replacing mine later this summer since it's just starting to bind a little.... what compressor would you guys reccomend? Preferably not one that's outrageously priced, but I'd rather we do this job once than buy a POS and waste our time.

[zigzag]

sorry to bring this thread back but i found that someone unplugged the electrical connector to the compressor and i cant find the damn thing anywhere.. can anyone take a pic of what the connector looks like and the wire colors? living here in san antonio sucks without a/c >.< thank you ^_^

[zigzag]

anyone? its reaching 90F down here and rising lol

[Prospeeder]

look around for a disconnected wire, its in there somewhere, prolly coverd in grease. It just randomly comes out of the harness somewhere. Just get under there and look

[zigzag]

i did look.. and look and look and look........ its not there.. i found a 2pin circle connector but it doesn't fit cause the one on the a/c compressor is oval shaped.... ill get pics soon to show you what im talking about.

now i did see 2 wires comming from the same sleeve of that 2pin circle connector both looked cut connected and cut again. perhaps that was my connectors wires, but i noticed when i pulled back the sleeve the 2 black wires were in bad shape and exposed.. how far back i dont know.... sucks though i need to get this crap figured out..

[zigzag]

i would of had this pic up the other day but my phone was being a major POS....

http://img697.imageshack.us/img697/7058/apr07001.th.jpg (http://img697.imageshack.us/i/apr07001.jpg/)

i don't know what this connects to, and it doesn't connect to the compressor because the conection on the compressor is oval shaped not round.. and believe me i tried connecting it....

any thoughts?

[turbokinetic]

i would of had this pic up the other day but my phone was being a major POS....

http://img697.imageshack.us/img697/7058/apr07001.th.jpg (http://img697.imageshack.us/i/apr07001.jpg/)

i don't know what this connects to, and it doesn't connect to the compressor because the conection on the compressor is oval shaped not round.. and believe me i tried connecting it....

any thoughts?

Yep. That is an A/C pressure switch connector. Look in the rear end of the compressor. I will look for a picture shortly!
David

[turbokinetic]

In the picture below, there are 2 pressure switches circled in Red. The upper one is mounted in the compressor. This is NORMALLY where that connector goes.

There are 2 more places it can be. The second place is in the compressor pressure line. The second switch (circled) is one of the hign presssure locations that could have a switch that fits that connector.

The thord location is in the tubeline marked in Yellow. Follow that to the car's right, and it will turn to a hose, then back to a metal tube. Anywhere along this line there may be pressure switches. They will be near the compressor (as shown) or on the section of tube that follows the right-side fender going forward towards the radiator.

Hope this helps!

http://68.209.87.173/87_Century/Modifications/Sys_install/ACpress_sw1.JPG

[zigzag]

ill see if i cant get under the car tomorrow and check it out.. does it go in one way?

also where do you fill the freon? is it the valve to the right of the throttle body near the cruise control?

[turbokinetic]

Yep the plug only fits the pressure switch one way. There is a slot on the side of the connector and a tab on the switch.

The charging port is on the line that goes near the cruise and TB. It may be on the drier bottle, too.

David

[Prospeeder]

better know what ur doin if your gonna try and charge it. If its 93 or older it will be R12, and will need to be retrofitted, so new Filter/Dryer and orifice tube is a minimum. Then you must replace the fittings, retro kits are easily avalible w/ the fittings. The Retro kits somtimes have Freon, stop leak, and oil. the system must have oil or compressor destruction will quickly occur. And its recharged to about 30-35 lbs running on a warm day

[zigzag]

wow i figured they would have changed over the newer freon them bastards >.< nope cant say i have the slightest clue what im doing other than filling the freon till the gauge reads in the green....

i am unsure, and correct me if im wrong, but dont they have an oil freon mix that supports both R-12 and the newer freon?

[turbokinetic]

wow i figured they would have changed over the newer freon them bastards >.< nope cant say i have the slightest clue what im doing other than filling the freon till the gauge reads in the green....

i am unsure, and correct me if im wrong, but dont they have an oil freon mix that supports both R-12 and the newer freon?

People WILL argue with me - but I know from experience (lots of it) that anything other than a system flush and full charge with new, clean oil for R134A is a temporary, marginal fix.

Having said that - yes you can mix in about 5 ounces of ESTER oil on top of the existing oil, and then use R134A. It will work pretty well, but may not last as long as a real flushed-out clean system would.

There are some inherant risks with A/C work and it would be wise to have someone with some experience do this. I say this only because of the safety issues dealing with compressed gases.

David

[Century7667]

People WILL argue with me - but I know from experience (lots of it) that anything other than a system flush and full charge with new, clean oil for R134A is a temporary, marginal fix.

Having said that - yes you can mix in about 5 ounces of ESTER oil on top of the existing oil, and then use R134A. It will work pretty well, but may not last as long as a real flushed-out clean system would.

There are some inherant risks with A/C work and it would be wise to have someone with some experience do this. I say this only because of the safety issues dealing with compressed gases.

David

Very good advice!

Ken T.

[deathamatend]

Check between the engine block and the A/C compressor. Two wire plug with locks on it. Might have to jack/ramp to get a good look for it. It is a wire harness feed from up top. Could be hidden in a grease pie. Go to U-DO-IT and power wash engine compartment I just use plain water rinse setting. Wiring will be much happier

[deathamatend]

I have another take on this situation. I would recommend going on Ebay and buying four to five cans of R-12. Small cans of R-12 can be bought by anyone until supply of them is gone. Now that being said you have to have equipment to charge A/C wether you have R-134A or R-12. I offer this angle due to the fact that A) the system may be just low and B) to open and sucessfully change system components and evacuate it is a carefully planned out job and you have to know what you are doing. A problem no one has mentioned is ALL the o-rings will fail on a R-12 to R-134A conversion. If the o-rings are not the "green" color ones they will all leak. Many conversion kits and installers omit this vital information. When they fail you will be far removed from going back and claiming a warraty issue. An important thing to remember a sucessful R-12 to R-134A conversion will require a new condenser (thing in front of radiator) R-134A performance is not quite as good as R-12 so the condenser is bigger to dissapate heat better. Otherwise it will not be as cold of an output inside the car as it would be with R-12.

The main thing and the most important one is there ANY pressure reading on the high and low side? If Yes: recharge with R-12. If No: any and all options are available.

[turbokinetic]

Thankfully, the A-body cars have large enough condensers that even the old ones work fine with R134A.

Proof? Here is a convincing image:

http://68.209.87.173/87_Century/Modifications/Sys_install/ICtest_fit.jpg

Even with the turbo intercooler blocking some of the airflow, and the original 1987-era condenser, you get this kind of performance:

http://68.209.87.173/87_Century/Restoration/AC_kickazz.jpg

This was flushed out, new oil, new drier, oriface valve, evacuuated, and charged with R134A. No other components were changed.

Thanks,
David

[Prospeeder]

With a food type thermometer my 6000's R12 hits 34 degrees, hah, my condensers beat the shit too. it would be worth while to find a 94-96 Ciera/Century to get the A/C condenser fan

[Century7667]

Thankfully, the A-body cars have large enough condensers that even the old ones work fine with R134A.

Proof? Here is a convincing image:

http://68.209.87.173/87_Century/Modifications/Sys_install/ICtest_fit.jpg

Even with the turbo intercooler blocking some of the airflow, and the original 1987-era condenser, you get this kind of performance:

http://68.209.87.173/87_Century/Restoration/AC_kickazz.jpg

This was flushed out, new oil, new drier, oriface valve, evacuuated, and charged with R134A. No other components were changed.

Thanks,
David

David,

Did you need a special orifice valve for the the R134a?

How do you determine how much refrigerant to put in?

Ken T.

[turbokinetic]

David,

Did you need a special orifice valve for the the R134a?

How do you determine how much refrigerant to put in?

Ken T.

I used a variable oriface valve, which works with any R12 or R134A compatible refrigerant. It really helps!

Somewhere I have pictures of the system repairs on this car. It was more of a modification of the hoses due to turbo install; than a repair, though.

David

[turbokinetic]

OH on the refrigerant charge amount!

It is 70% by WEIGHT of the R12 carge specification. It works out to 3 cans of R134A for our cars. You can take that one to the bank, too! :)

David

[Zaloryan]

OH on the refrigerant charge amount!

It is 70% by WEIGHT of the R12 carge specification. It works out to 3 cans of R134A for our cars. You can take that one to the bank, too! :)

David

Just last week I did some DIY A/C work. Last April I replaced the compressor & poured in some PAG150 (Oil specified for GM R134 systems. If you use R12, ESTER is specified. I have heard that different oils will work fine. I am not disputing that.) After having a vacuum test done, the system was filled and immediately leaked out. As it would be, the A/C line running from the evaporator (left of the master cylinder) to the drier (front driver side corner of engine bay) had worn a hole in it. Over the years, the plastic lines for the trans(?) had worn on the A/C line and allowed a small hole to develop.

I could not find one of these hoses for sale at the parts store, ebay, etc. They all have the suction & discharge line which bolts to the compressor. Also, these 3300s are hard to come by around in the NW area of Arkansas as well as southern Arkansas. (Maybe I don't know where to look. Haven't tried Little Rock yet) I picked up a 1993 3300 hose and the evaporator fitting was different! Well that won't work. :( Back to the old hose. So I went by a shop that makes high pressure hydraulic hoses for agricultural & industrial applications. They cut the metal part of the line out, and put some new fittings in and a new rubber hose section on. The only downside to this was the hose diameter was larger so I couldn't run the hose behind the wiper motor like the stock hose was. No problem. Routing still wasn't an issue. Still leaked after filling. I said heck with it, I need my money for other things.

Come this spring, I decided to try it again. I installed a retrofit kit. (Available at parts stores. Just two fittings that fit over the ones on your system.) I pulled the hose, installed two green O-Rings and put a little bit of PAG150 oil on each end. Re-installed the hose and had a vacuum test done. The system could hold almost 15 pounds of vacuum. I thought why not? I put in two 13 ounce cans of the R134 & wha-la! It cools quite well, but not 32 degrees cold. It's colder than most cars I've been in (except for the brand-new ones) but could certainly be colder.

I didn't put in any more refrigerant because the gauge on the fill hose indicated at the top of the green arc. I didn't want to push my luck, so I said it was fine. Guess what? It's cold. I like it. :)

[Century7667]

OH on the refrigerant charge amount!

It is 70% by WEIGHT of the R12 carge specification. It works out to 3 cans of R134A for our cars. You can take that one to the bank, too! :)

David

The reason I ask is that I had A/C service done to my '95. I just never invested in all the tools for A/C repair...but I'm getting tempted. So, A/C and Auto Trans, I don't do. Anyways, I was getting 50 degrees on a good day on the '95 Century that uses R134a from the factory. They told me, we'll have to suck it down and the only way we'll know to put the proper amount in it, then do a leak test. I said, "Ok" and it turned out to have an evoporator core leak. They replaced the evaporator, and now I get 40 degrees...which is a great improvement.

However...the '96 Buick get's 34 degrees, and I just saw you getting just above freezing. The compressor looks like it had been replaced recently, and I'm wondering why do I only get 40 degrees? It's not icing up either. I just get 40. Any ideas as to what I can look for?

I'm about ready to put my hands on it.

Thanks,
Ken T.

[Prospeeder]

bent condeser fins, somtimes stuff accumulates on the front of it too. Clogged orifice tube, low refrigerent, blend door not closing all the way are just a few things that can cause so so a/c operation

[subordinate]

Any insight to as how much it would cost to flush and retrofit the R-12's (to R-134a) and top it off? (to get a shop to do it)

Thanks.

[Century7667]

bent condeser fins, somtimes stuff accumulates on the front of it too. Clogged orifice tube, low refrigerent, blend door not closing all the way are just a few things that can cause so so a/c operation

Clogged orifice tube - Hmmm, I'd hope they got that with the evaporator, but I can't remember.

Low Refrigerant - What can you do? You cant' do your own A/C work anymore, and you pay people $$$$$, you can only pray they can get it right.

Blend door - Possible.

Another thought I had was they didn't replace the foam where the hoses go into the evaporator core. I dunno.

Ken T.

[subordinate]

Yea, Compressor off and noise = Pully bearing
Compressor noise only when A/C on = Compressors bad

The clutches typicly either slip or dont work period

Since my a/c is non-existent, I tried recharging it with some R12a, which is compatible with R12. The a/c refrigerant is call Redtek.

And I think my compressor is dead. The only noise is when heat is on, which creates a charging sound/cycling sound, otherwise, there is no sound when I tried in a/c mode.
So would this be my compressor?

And reading up on it, to remove any component of an a/c system, I would have to remove all the refrigerant?

Dang, I might have to bring it to a a/c shop.

[Prospeeder]

Hmm, is it low on refrigerant? If it is full, set the a/c on, is the compressor coming on and running? If not, then take the low pressure switch, disconnect it, and jump it with a paper clip and see if the compressor comes on. if it does, you have a bad low pressure switch, or low refrigerent. If it still isnt engaging the compressor, you may have bad wiring to the clutch, or even possibly a bad clutch. You can take jumper leads and use a battery to jump the compressor cutch, its a pain on these cars but possible. If its running and just not getting cold. Things like plugged up orifice tube, obstructed, dirty, or clogged condensor, no cooling fan operation, junk in the evaperator box can cause poor cooling. Also the V5 compressors we use are a variable compressor, the valving body thing for it can go bad and the compressor runs but no refrigerent or not enough circulates, I beilive thats my TGPs a/c problem.

[zigzag]

so can i pull a compressor off any car and use it.. or are there specific kinds of compressors? im thinking my compressor is bad cause it was unhooked when i first bought the car.... i know ill have to take it to a shop and have them flush the system put in the oil and charge it up.. maybe i can find a shop that does free a/c check..

[Prospeeder]

According to my computer really any compressor off a late 80's early 90's 3300 or 3800 car should be fine

[zigzag]

was hoping i could just pull one off any car XD most of these cars here in texas that old dont have running a/c XD we use it like crazy here in texas.. most compressors just burn out..