AC Repair Insight Needed

[GoldenEagleFan]

I need to have my condensor replaced as the fitting at the lower left (looking from front) cracked at leaked my freon and lubricant out. Last time I had the system charged the comment was made that my compressor was louder than normal and may also need to be replace in the future, so I was planning on doing this at the same time. I also understand the drier needs to be replaced whenever the system is opened up. I was thinking about doing the mechanical work myself and then taking the vehicle to an AC shop to be charged.

My questions are:

1) Looking through the Bently manual this all loooks fairly straight forward for a DIY job. IHowever, is there a trick way to get the condensor out without taking off the front bunber and grill?

2) Anything I should know before getting into this job? Should I replace all o-rings I encounter? Any other precautions or words of warning.

3) Any suggestions on a good source of parts? Should I use new or rebuilt compressor? Any brands to stay away from?

Any other tips, techniques, gotcha's would be appreciated.

1994 525i, 160,000 miles, manual

[kick7ca]

I have to do an almost identical repair.

I think removing the front bumber is the only way to remove the condensor. Removing the bumper is actually easy, it slides forward and off after a couple of bolts.

I have to replace condensor and possibly 1 or 2 hard lines, and the drier, then I'll take it for a free test to see if it holds pressure, then I'll pay to have it filled.

[peterllo]

Keep posting on how you make your way through this. My '94 525 has some sort of leak. I temporarily fixed it with a can of 134a with the charge gage obtained from Advance Auto. I plan to get dye and charge it again and go forward from there. Judging from the 175K and the fact I just replaced the radiator and trans oil cooler within the last year, my condensor is on the short list.



I need to have my condensor replaced as the fitting at the lower left (looking from front) cracked at leaked my freon and lubricant out. Last time I had the system charged the comment was made that my compressor was louder than normal and may also need to be replace in the future, so I was planning on doing this at the same time. I also understand the drier needs to be replaced whenever the system is opened up. I was thinking about doing the mechanical work myself and then taking the vehicle to an AC shop to be charged.

My questions are:

1) Looking through the Bently manual this all loooks fairly straight forward for a DIY job. IHowever, is there a trick way to get the condensor out without taking off the front bunber and grill?

2) Anything I should know before getting into this job? Should I replace all o-rings I encounter? Any other precautions or words of warning.

3) Any suggestions on a good source of parts? Should I use new or rebuilt compressor? Any brands to stay away from?

Any other tips, techniques, gotcha's would be appreciated.

1994 525i, 160,000 miles, manual

[joshua43214]

If your spending that much on it, see if you can budget in the hoses too, you will thank yourself later. The only problem you may run into is sometimes the fitings seize onto the condensor. not a major issue since you are replaceing it, just let them break off and use a socket to remove the fitting from the hose.

[Jon K]

You must take the buumper and grill off to get the condensor out - you also have to remove the Aux fan.

[SchnellE34]

I just had a pressure test done and they found a leak in the same place on my condensor. I am going to replace it myself. I was told the compressor is louder than it should be but I don't agree, and am going to leave it in for the time being.

Not sure what condensor I'm going to buy but this drier (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=6630819814&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1) looks ok. Anyone else agree? I am planning on replacing all o rings. Is there somewhere I can buy the entire set of o rings for the a/c system? My local auto parts store has a large box of o rings for $20 that looks ok.

What about the oil? Should I buy some to put in the system or does the shop do that with a recharge?

I have been researching the subject on the board the past week and found the consensus is that replacing with used parts is not a good idea.

[Blitzkrieg Bob]

Changed out the condensor in less than an hour by removing the radiator from the inside.

drain coolant

unclip shroud

remove hoses and trans cooler lines

uncilp radiator and remove

uncilp side shrouds

remove the passenger side access panel by the fog light and remove the fittings

remove the two bolts at the top of the condensor

tilt condensor to the rear and un plug the aux fan.

and it's out!

[Blitzkrieg Bob]

condensor, drier, and compressor on my car.

Shop around for the parts, make sure they have BMW part#s to help make sure you get the right stuff. (drier and condensor will pretty much fit all E34s, it's the compressor that has to be matched to that application)

I picked up some O rings from an A/C shop and also the dealer. (Gotta be for A/C, not hardware store stuff)

Buy extras, cause if you drop one...they tend to disappear, and you don't want the system sitting open while you run off to find more O rings.

The noisy compressor may be low on oil. You can drain the oil look at it and replace it. Don't just add, too much is just as bad as too little. you need to add the right amount and type of oil for that compressor.

Be advised, that refrigeration work is not something to jump into without a some experianced help/guidance and proper tools....you can spend $$$ refixing stuff, or frost bite.

[SchnellE34]

Much appreciated sir.

[Jon K]

I have all of these items for sale from a 1992 BMW 525i everything looks to be in good shape and worked when removed from teh car.

In fact I have 2 compressors if you'd need them.

[SchnellE34]

check your pm's

[Jon K]

replied

[Chris'91'525i]

I just had a pressure test done and they found a leak in the same place on my condensor. I am going to replace it myself. I was told the compressor is louder than it should be but I don't agree, and am going to leave it in for the time being.

Not sure what condensor I'm going to buy but this drier (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=6630819814&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1) looks ok. Anyone else agree? I am planning on replacing all o rings. Is there somewhere I can buy the entire set of o rings for the a/c system? My local auto parts store has a large box of o rings for $20 that looks ok.

What about the oil? Should I buy some to put in the system or does the shop do that with a recharge?

I have been researching the subject on the board the past week and found the consensus is that replacing with used parts is not a good idea.

I have a NIB reciever drier for $35 shipped if interested. Have no need for it now since all I needed was a new A/C belt (long story). (edit:cjwilson2005ATgmailDOTcom)

If your compressor is bad you may want to flush out the complete A/C system with solvent to get the old oil and any bad compressor particles out of it.

[SchnellE34]

where did you get it? what is the brand?

[Tiger]

The thing about compressor... they will go bad from wear and tear... but the deal is finding cheapest rebuilt unit... like this... You can cross-reference and buy the same exact unit... Yours is Nippondenso 10PA17C.

Here is a rebuilt one for $145
http://cgi.ebay.com/ebaymotors/91-99-BMW-M3-323-325-328-525-A-C-COMPRESSOR_W0QQcmdZViewItemQQcategoryZ33543QQitemZ 8067544261QQrdZ1QQsspagenameZWDVW

It cost about that much to have yours rebuilt. Keep searching under 10PA17C... there is someone selling brand new one with drier and expansion valve for $289 total...

http://cgi.ebay.com/ebaymotors/NEW-BMW-A-C-COMPRESSOR-KIT-325-525-535-540-735-740_W0QQcmdZViewItemQQcategoryZ33543QQitemZ8068067 980QQrdZ1QQsspagenameZWDVW

Also condenser new by Nissen for $150 including shipping...

http://cgi.ebay.com/ebaymotors/New-A-C-Condenser-BMW-525i-530i-540i-735i-740i-750i_W0QQcmdZViewItemQQcategoryZ33578QQitemZ806745 7640QQrdZ1QQsspagenameZWDVW

With the above prices, you are simply buying both for the price of one new condenser...

[SchnellE34]

I think I am going to buy the condensor from BMA for $50 more. Don't really like buying mechanical or electrical parts from eBay. I like to be able to talk to people on the phone not just email as most eBay sellers do communication. Plus I want to get all o rings and BMA has those also.

I am going to reseach the compressor and it's oil situation (i.e. check the bentley and the board) to find out how to drain and refill the oil as Bob was talking about. Probably put up a new thread if I have anyquestions.

[joshua43214]

If you buy used parts, make sure they use the same refrigerant. I seem to remember JonK's being r12, a 94e34 should be r134a. Dont buy a crappy Ebay dryer, get OEM.

let the AC guy add the oil, make sure he knows what you replaced and tell him he has to add oil.

[SchnellE34]

I was hoping you would chime in here Josh. I'm looking at the Bentley now, it doesn't say anything about draining oil out of the compressor. How do I do that? Do I have to remove the compressor? I am reading all of the warnings and cautions about opening the system up to perform work. I just had a leak test and they only put a little refrigerant in with some dye, should I have any problem opening it up to replace the condensor and drier?

I will be capping open holes to block dust and dirt and replacing all o rings.

EDIT: then having a shop vacuum and refill with refrigerant and oil.

[joshua43214]

To drain the compresor, you must remove it and stand it over a clean cup and let it drain for a while, then slowly rotate the shaft to get the last of the oil out. You only need to drain the compressor if you are replacing it, and that is only to verify how much oil is in it. The new compressor should come pre-oiled, there will be a slip inside the box stating whether it has oil or not, and how much oil it should have if its empty. It will say something like, drain old compressor and measure oil, if 3oz or less, add 3oz of oil. if more, add the amount removed.

The dryer may also come with a slip stating how much oil to add, if it does, give it to the AC guy, if not, he has a chart telling him how much oil to add depending on what part was replaced and he can adjust that from experience if the part is bigger or smaller than standard.

You seem to be on the right track, I would maybe hold off on the dryer until you replace the compressor, since you will just replace it again when you do the compressor. Cleanlyness is the key, I like to clean the conections with brake clean before I separate things to make it easier to keep clean. Use r12 oil on the O-rings, not pag oil. I just pile them on a clean rag and pour a lidful of oil over them then pick them up with a pick tool. Don't forget to get new service caps, or have the AC guy put new ones on when he charges it.

[Jon K]

Does an R12 vs R134 dryer matter? I have a drier here worked perfectly on my R12 system if you want it.

[Blitzkrieg Bob]

you don't want to leave the system open, and un pressureized while doing the work over a period of time.

As far as the oil...Try to search the web for information on your compressor.

To drain and check the oil, you will have to remove it from the car, pour out the oil and measure it.

I have seen several sites with specs that included oil and capacity. Yours is R134, so I would guess PAG oil would be recomended.

I had an older car that used three differant compressors Bher, Bosch, Seiki (none exactly the same), so I had to hunt down a Seiki, with the correct side switch, manifold and mount. I did not want to do the adapter thing.

Good luck

[joshua43214]

Does an R12 vs R134 dryer matter? I have a drier here worked perfectly on my R12 system if you want it.

They use different oils and are not really drainable. Maybe put it in a big ziplock bag and let it drain that way? Dunno, they are normaly replaced during a conversion, but you could get away with using it I bet if on a tight budget.

[SchnellE34]

Josh,

I was not planning on replacing the compressor. When the system was checked they told me it was making too much noise and should be replaced. When I listen to it, the noise is not very loud at all and it was recommened by a member of this board to replace the oil in the compressor.


If I were to drain the oil would I have to replace it before reinstalling the compressor or can the oil be replaced with a recharge? This is PAG oil that I put in the compressor, right?

Thanks for the tip on keeping everything clean. But r12 oil on the o rings? on a r134 system? I keep hearing about the 'service caps' what are they? like a cap over each line connection?

[Blitzkrieg Bob]

replace the compressor.

oil may slove the noise problem, but if it is the brearings, then a failure could send crap all though the system.

Then it's back to flushing all the lines, condensor, evaporator and changing the drier, and expansion valve and a new/rebuilt compressor.

[joshua43214]

There are different types of pag oils, so make sure you use the correct oil, the underhood sticker will say the type of oil to use, or the AC guy will have a chart showing what oil is used on your car/compressor type. There is one type of oil that is treated like a "universal" oil, but it should only be used if there is no info on the car at all. A parts store that caters to professionals like NAPA or CarQuest is the better bet for buying pag oils rather than Autozone or PepBoys that caters to amateurs. NAPA will sell you a clearly labeled bottle of oil and will have more trustworthy references for your car if you have lost the underhood sticker.

If the compressor is drained, it must be filled with the proper amount of oil before its installed. add oil to the suction side, turning the compressor gently back and forth, don't look don't the pressure side, they tend to burp up a shot of oil doing this.

Pag oil attract moisture, so if used on o-rings, it will attract any contaminates in the air, including salt, and can cause the fittings to permantly seize together.

The service cap is the cap over the connector for charging, it is the primary seal, not the schreader valve inside it.

[SchnellE34]

Wow, great information thanks very much guys.