What caused slow leak on your A/C?

[perelet]

I have slow leak in my A/C. Will need to replace parts. In case if you had same - please let me know what was it.

1. Compressor
2. 2 flex hose$$$
3. Condencer
4. Evaporator.


Thanks.
Oleg.

[TxGR8White]

none of the above.
It is usually the o-rings that give out, especially after 20+ years....

[perelet]

Steffen, thanks.

#6, #7 & #8? What locations are most suspect-able?



Oleg.

[olinjohnston]

6, 7, 8...all locations can potentially leak

perelet, what are the last 7 digits of your VIN?

[perelet]

...

perelet, what are the last 7 digits of your VIN?

Thanks! Last 7 vin digits: cb75200

Oleg

[TxGR8White]

Correct - ALL the o-rings. They really need to be replaced as a complete set, especially after all these years. No sense only doing the ones you "think" might be at fault - remember, they are ALL the same age...

[perelet]

Found few more #7,8,9,10




Are those reachable by removing glovebox and side pass side panel?

Oleg.

[TxGR8White]

I used a complete O-ring kit (assortment) that had more than enough to do the job, and it cost far less than sorcing each o-ring from BMW (By the way, some of the sizes are not quite correct in the listing on Realoem. It is best to just match them up as you go.

[perelet]

Is there part # for o-ring set?

PS. Interesting I have 911 (time trial/track car) of same vintage and there compressor was leaking. Also a bit younger (my daily driver) jeep wrangler and flex hoses leaked on it.
Oleg.

[legoman67]

Is there part # for o-ring set?
Oleg.

realoem.com, no oem kits.. but there arent that many orings.

or you buy a set of assorted O-rings from a local autoparts store and use the ones that fit, i think that is what Tx is referring to.


i replaced them all when i did my engine swap... no leaks and cold AC

[Mike in CT]

There are five different sizes and cheap. I just ordered a bunch of each size from Autohaus.

Had leaks at the condenser fitting:







and one of the braze joints at the evaporator:



You could use a florescent dye and look for the leak as shown in the photos above.

Evaporator is removed by removing glove box and sliding out.





Be careful with the temperature sensor probe on the opposite side when you insert the evaporator. With the BEHR unit I put in a couple of weeks ago the hole in the evaporator for the probe was closed off and need to be opened up with an awl.

Having change the evaporator twice, I would not want to do this unless nessesary. Oil film on windshield?

Yes, one of the O-Rings is mis-identified. Can't remember which one.

[Dr. T]

Condenser...leaked twice. Telltale sign was an oil-spot on the grille.

[Mike in CT]

Condenser...leaked twice. Telltale sign was an oil-spot on the grille.

And can be an easy R/R. Don't even need to remove the radiator. If the allen head bolts are corroded (like above), could cause some difficulty.

[TxGR8White]

I bought a set at Harbor Freight the second time around. Just make sure you grab the green ones. The first time I did an o-ring replacement, I blindly went with what realoem had listed. Not only was this expensive, but only when I had everything apart did I find out that I didn't have all the right ones. The Harnor Freight kit will easily do 5 or 6 systems.

[perelet]

Replaced o-rings. Will give it few months to see if leak is fixed. In addition to pics posted by Mike Here are some pics/illustrations:

discharge system.

Dryer lines

Remove plastic covers on pass side:



Dryer is there




Undo hex bolts on lines. I removed dryer to have easier access to seals:



next

Condenser lines

Remove plastic cover at top of nose panel.



use long extension and remove bolts:




For me it was hard to reach from top, so I removed front lip:



then unbolted horn:



after that I had access to lines and seals:

Compressor lines

They are accessible from top. Nothing needs to be removed:




Unbolt bolts, remove lines:

Engine compartment coupling

Again, nothing to remove:

expansion valve

A bit of pain to get to...



and then keep removing stuff until you get to it:



getting closer:





To remove screws you'll need torx screwdriver:



And here it is:




Last is torx screw on top of it - also pain to get to. I run out of batteries here ....



After that vacuum the system:



and charge:




Oleg.

[Cefalu]

PO of my '95 840Ci paid the dealer close to $1,500 to replace the evaporator. The dealer said that it put a sniffer in the dash outlet and detected refrigerant. Sounds like it was probably just the O ring.

[perelet]

PO of my '95 840Ci paid the dealer close to $1,500 to replace the evaporator. The dealer said that it put a sniffer in the dash outlet and detected refrigerant. Sounds like it was probably just the O ring.

Cefalu, thanks! Mike also mentioned evaporator, so statistically it does break. I'm not claiming victory - time to show. Replacing seals is definately one of least expensive repears on e31 i did, so surely is it 1st logical step.

Oleg

[Xpressions]

Has anybody replaced the actual pipework here in this picture? the two pipes and fitting adjoining the AC condensor, mine are quite badly corroded, and id like to replace them, looks like its definitely bumper off, but just not sure yet were the metal pipe ends?! real OEM is just not accurate. Is there another join before the AC compressor?

[perelet]

Has anybody replaced the actual pipework here in this picture? the two pipes and fitting adjoining the AC condensor, mine are quite badly corroded, and id like to replace them, looks like its definitely bumper off, but just not sure yet were the metal pipe ends?! real OEM is just not accurate. Is there another join before the AC compressor?

Xpressions, here are pics I did when I replaced radiator and headlight assembly - you can see A/C lines clearly:







My guess is you'll need to take radiator and headlight (pain to put back) also air intake.

Oleg.

[perelet]

Update. Little bit more than one month passed. All refrigerant leaked out .

Well, I had dealt with this car for awhile I had doubts that $15 can fix anything on the beast. Time for $$$ again.


Oleg.

[Mike in CT]

Oleg,

Did you try the addition of a can of refrigerant with fluorescent dye and pick up the fluorescent flashlight/yellow goggle kit at a NAPA or PEP Boys to pinpoint the leak? Works quite well. The AC, at least on my '97, works great when everything is in order. And everything except the lines is new.

Mike

[perelet]

Mike, I did. I do see leak at front of compressor. Also almost everybody had to replace evaporator, there was even recall for it on some E31 years.

I'll start with compressor and evaporator and will go slowly from there, avoiding divorce and bankruptcy

Oleg.

[Ahmed303]

Oleg,

Please post the source and price of the compressor and evaporator when you replace them. My AC is fine for now but might as well for a 18 year old car.

[Mike in CT]

Mike, I did. I do see leak at front of compressor. Also almost everybody had to replace evaporator, there was even recall for it on some E31 years.

I'll start with compressor and evaporator and will go slowly from there, avoiding divorce and bankruptcy

Oleg.

To avoid the divorce issue, I just point out that the the time spent working on the 8 keeps me out of gin mills.

[zenn0ne]

To avoid the divorce issue, I just point out that the the time spent working on the 8 keeps me out of gin mills.

Hahaha I agree 100%

Sent from my Hoopty on full boost!!