Air Conditioning Repair

**hunteryeager** · 07-05-2017, 07:46 PM

Hello Everyone!

I recently purchased my 1989 325i Convertible back from a friend I sold it to 10 years ago due to leaving for college. Trust me, I was not happy about it. When she bought the car from me, she intended for it to be a weekend cruiser but only amassed a whopping 3,000 miles in those 10 years. Much to my chagrin, the car was not as well kept as when I owned it. In 2007 when I sold it to her, the air conditioner worked perfectly. Now, the compressor has been bypassed (belt removed) due to it seizing on a drive to New Orleans. Obviously the compressor is bad and I know from experience when replacing the air conditioning system in my 1994 MB C220, if the compressor needs to be changed, so does the condenser, drier, etc.. If I elect to repair my air conditioning system to restore it to the condition it was in when I sold it, what components do you suggest to replace? I've also read about the lack of availability of compressors for this car due to there being a change in manufacturers during that time or something. This may be the only component of the car that needs to be repaired by a professional, I can handle the rest.

Any advice you can offer would be an amazing help.

**BATTLERATTLER** · 07-06-2017, 01:27 AM

I have no idea but I have no AC either.

**Jeffnhiscars** · 07-06-2017, 09:06 AM

You dont say whether the system was converted to r134 but if not, now would be the time to do it. The biggest challenge is the compressor, not so much that you cant find a good, inexpensive, r134 specific compressor, but rather the mounting hardware is NLA. If you go with a stock compressor they are fairly expensive and despite having upgraded seals to tolerate r134, they are still designed for r12 operating pressures so will be less than optimal. Having said that there are lots of r 134 systems running on OE compressors and doing quite well. You just have to choose your poison...mounting PITA VS costly OE compressor.

Beyond that, a PF condensor will help and for r134 you want to upgrade as many hoses as your budget allows to barrier type hose which will better retain the smaller r`134 molecules. Again, if converting you will need to flush the old system very thoroughly and change the oil from mineral to PAG as well as replace the expansion valave with an r134 valve.

questions to ask yourself:

is the system converted (look for adaptor fittings)
stock replacement or mode4rn compressor
whats your budget and how much can you do yourself

**richardodn** · 07-07-2017, 06:52 AM

An 89 might very well already have the later R134 barrier hoses. BMW started using those before going to R134 in the last production years

**sienayr** · 07-07-2017, 10:10 PM

This is a notes dump of all the research I've done on compressor replacement. A little raw but hopefully useful. If you can handle the rest then you can probably handle AC stuff too.

http://www.r3vlimited.com/board/showthread.php?t=246743

Rock Auto Parts
Compressor, dryer and pressure switch
$265
http://www.rockauto.com/en/moreinfo....011700&jsn=387

Condensor
$106
http://www.rockauto.com/en/moreinfo....sn=381&jsn=381

http://www.rockauto.com/en/cart
FOUR SEASONS 59976 R
-12 TO R-134a RETROFIT KITS AND FITTINGS - LOW SIDE

FOUR SEASONS 59978
R-12 TO R-134a RETROFIT KITS AND FITTINGS - HI SIDE

FOUR SEASONS 26773 AC System Seal Kit

FOUR SEASONS TSR0911 Tech Select A/C Kit Reman

http://www.compressor-intl.com/index.html

http://www.thecompressorwarehouse.com/results.cfm

http://www.techchoiceparts.com/inventory

https://www.youtube.com/watch?v=MangGmPZc6g

https://www.youtube.com/watch?v=Zn9N5sypuME

https://www.youtube.com/watch?v=sh-KIjAqh-A

pull vacuum before replacing all o rings
flush system

compressor repair parts
http://max-ac.com/10P15E_c_22506.html

The compressor gasket set contains mostly o-rings: 1) three large o-rings for resealing the case sections, 2) four small o-rings for resealing the suction and discharge fittings - where the shraeder (sp?) valves are located (you know, like the valves on a bicycle tire/inner tube), 3) one small o-ring for the shaft seal seat (a duplicate for the one in the shaft seal kit), and 4) five washers to use with the head bolts (again, duplicates for the ones in the shaft seal kit).

compressor diagram
http://www.acsource.com/10p13c10p15c...breakdown.aspx

repair diy
http://www.pelicanparts.com/techarti...so_rebuild.htm

http://members.rennlist.com/elsies91...nsorebuild.htm

system picture
http://s115.photobucket.com/user/bea...nes-1.jpg.html

refrigerant
http://www.harborfreight.com/18-oz-a...uge-97275.html

http://www.realoem.com/bmw/enUS/part...BMW-325i&mg=64

64521386256
10P15E
Denso

o rings
http://www.r3vlimited.com/board/show...5&postcount=11

oil viscosity
https://docs.google.com/file/d/0B6qM...t?pref=2&pli=1

http://www.rockauto.com/en/moreinfo....011700&jsn=368

http://www.techchoiceparts.com/inven...-ac-compressor

http://www.e30tech.com/forum/showthread.php?t=113435

http://www.exx.se/techinfo/docs/r134a_retrofit.pdf

http://www.compressorsoftheworld.com...ompressors.php

NipponDenso 10p15e compressor $30
Vapor hose from firewall to compressor w/ 5/8" tube fitting $10

Buy the following new:
Receiver-drier $20
O-rings all around $3
R134a expansion valve $20
Compressor-to-condenser barrier hose $30

Drain the oil from the compressor and rinse with mineral spirits.
If you have an air compressor, flush some mineral spirits or other evaporating cleaner through each hose individually.

**thejlevie** · 07-08-2017, 06:07 PM

If the compressor seized, the entire system must be flushed and some parts other than the compressor may need to be replaced. Unless you have the training and equipment this could be a job best done by a pro.

**Thecatmilton** · 07-16-2017, 12:13 AM

I flushed the system in my e21 out with acetone. I think it did a good job due to the green/brown color it had when it came out. I used acetone as it shouldn't leave any residue behind. After flushing it, I dumped lots of compressed air through the condenser and evap pipes to ensure that it had all evaporated. The blow guns are okay for part of the flush, but dont provide enough airflow to get everything out.

I would suggest using ester oil when converting to r134a as its compatible with r12 and r134a. Ester oil also doesn't react badly by becoming acidic if it comes into contact with any residual r12 mineral oil left in the system like PAG oil does. I was able to get a gallon of FJC ester oil on amazon for around $40.

**thejlevie** · 07-16-2017, 04:03 PM

Compressed air can contain a lot of moisture, which is why a good pro will use dry nitrogen. Once sealed up, evacuate the system overnight or longer to pull as much moisture out as possible before charging. Charging is best done by the weight of the charge.

**Brianjasper23** · 07-21-2017, 01:27 PM

I think you should consult with a bmw dealer.

**superj** · 07-21-2017, 02:04 PM

I have always done my own, e21 ,multiple e30s, Cherokees, grand Cherokees, wranglers, pt cruisers, and camrys. if you are careful, you will be fine doing it in the garage. I am not an ac guy and mine always blew out in the low 40s at the vent

**15Michaeljoseph** · 07-22-2017, 08:04 PM

Originally Posted by Brianjasper23

I think you should consult with a bmw dealer.

This is probably the worst first post ever. Spam?

**E30Garage** · 07-23-2017, 02:04 PM

Originally Posted by sienayr

This is a notes dump of all the research I've done on compressor replacement. A little raw but hopefully useful. If you can handle the rest then you can probably handle AC stuff too.

http://www.r3vlimited.com/board/showthread.php?t=246743

Rock Auto Parts
Compressor, dryer and pressure switch
$265
http://www.rockauto.com/en/moreinfo....011700&jsn=387

Condensor
$106
http://www.rockauto.com/en/moreinfo....sn=381&jsn=381

http://www.rockauto.com/en/cart
FOUR SEASONS 59976 R
-12 TO R-134a RETROFIT KITS AND FITTINGS - LOW SIDE

FOUR SEASONS 59978
R-12 TO R-134a RETROFIT KITS AND FITTINGS - HI SIDE

FOUR SEASONS 26773 AC System Seal Kit

FOUR SEASONS TSR0911 Tech Select A/C Kit Reman

http://www.compressor-intl.com/index.html

http://www.thecompressorwarehouse.com/results.cfm

http://www.techchoiceparts.com/inventory

https://www.youtube.com/watch?v=MangGmPZc6g

https://www.youtube.com/watch?v=Zn9N5sypuME

https://www.youtube.com/watch?v=sh-KIjAqh-A

pull vacuum before replacing all o rings
flush system

compressor repair parts
http://max-ac.com/10P15E_c_22506.html

The compressor gasket set contains mostly o-rings: 1) three large o-rings for resealing the case sections, 2) four small o-rings for resealing the suction and discharge fittings - where the shraeder (sp?) valves are located (you know, like the valves on a bicycle tire/inner tube), 3) one small o-ring for the shaft seal seat (a duplicate for the one in the shaft seal kit), and 4) five washers to use with the head bolts (again, duplicates for the ones in the shaft seal kit).

compressor diagram
http://www.acsource.com/10p13c10p15c...breakdown.aspx

repair diy
http://www.pelicanparts.com/techarti...so_rebuild.htm

http://members.rennlist.com/elsies91...nsorebuild.htm

system picture
http://s115.photobucket.com/user/bea...nes-1.jpg.html

refrigerant
http://www.harborfreight.com/18-oz-a...uge-97275.html

http://www.realoem.com/bmw/enUS/part...BMW-325i&mg=64

64521386256
10P15E
Denso

o rings
http://www.r3vlimited.com/board/show...5&postcount=11

oil viscosity
https://docs.google.com/file/d/0B6qM...t?pref=2&pli=1

http://www.rockauto.com/en/moreinfo....011700&jsn=368

http://www.techchoiceparts.com/inven...-ac-compressor

http://www.e30tech.com/forum/showthread.php?t=113435

http://www.exx.se/techinfo/docs/r134a_retrofit.pdf

http://www.compressorsoftheworld.com...ompressors.php

NipponDenso 10p15e compressor $30
Vapor hose from firewall to compressor w/ 5/8" tube fitting $10

Buy the following new:
Receiver-drier $20
O-rings all around $3
R134a expansion valve $20
Compressor-to-condenser barrier hose $30

Drain the oil from the compressor and rinse with mineral spirits.
If you have an air compressor, flush some mineral spirits or other evaporating cleaner through each hose individually.

Thanks for sharing all this info I'm sure it will come in handy when I decide to do the conversion on my vert.

**T77911S** · 07-24-2017, 08:10 AM

you can flush all the other parts of the system.
new comp, dryer, and expansion valve.

my 88 has r134 in it, looks factory.

**E30Garage** · 07-24-2017, 12:38 PM

I don't know if this is any good, just found this R12 substitute freon, it appears people are buying it for their R12 systems.
http://www.ebay.com/itm/6-XL-CANS-R12-SYSTEMS-COMPATIBLE-MAXI-REFRIGERANT-18oz-ea-RECHARGE-1994-OLDER-/112412755729

**E30Garage** · 07-24-2017, 12:47 PM

Maxi-Frig vs. R12 A/C refrigerant

Here is test data using a standard dial type thermometer, comparing R12 and Maxi-Frig. Test was run using recirculated air only, not vented outside air. This was done to establish the cooling capabilities of each in as much of a controlled environment as possible.

Vehicle: Black '90 X-cab w/Maxi-Frig
Base Temp: Outside: 85.........Inside Cab: 118........Vent no A/C:112
Humidity: 57%
Time of Day: 3:40pm
A/C Temps
@1250rpms:...5mins.....10 mins....13 mins
Vent Temp:......74.............72.............70
Cab Temp:.......96.............92.............88
A/C Temps:....................10 mins......13 mins
@2700rpms Vent Temp:....70................68
Difference in Cab Temp after 13 mins -30 degrees.
Difference in Vent Temp after 13 mins -44 degrees.

Vehicle: White '91 X-cab w/R12
Base Temp: Outside:85.......Inside Cab:103........Vent no A/C:97
Humidity: 57%
Time of Day: 4:00pm
A/C Temps
@1250rpms:...5mins....10 mins.....13 mins
Vent Temp:......54...........45............45
Cab Temp:.......88...........80............74
A/C Temps.....................10 mins.......13 mins
@2700rpms Vent Temp:.....43 .............42
Difference in Cab Temp after 13 mins -29 degrees.
Difference in Vent Temp after 13 mins -55 degrees.

Both trucks were sitting side-by-side and had been in full sun for 7 hours at the time of the test. Both truck's X-cab windows are limo tinted, the Black '90's driver/passenger side windows are tinted at 40% smoke, whereas the White 91's are stock, other than that they are identical.