BMW E24 AC upgrade(AS OF 2016)

[rlkrlk]

It's 20 low side and around 130-135 high when at 2500rpm. I tried adding more and the low side started going up. Adjusting also increases the low side vent temps and pressures. I did this when it was 70 out so hopefully it'll be warmer and I get time to test tomorrow.

You could try adding less, as well.

;-)

Cheers,

Ray

[n2bimmer]

A few weeks ago i had a A/C shop sort things out and charge her up. She blows cool air but on hot days its just cool, not cold. I also feel like there is so much glass and sun coming in the air doesn't get cold enough. Tint is not an option.
I was thinking maybe have the 134 removed and charged with r12? Would that get me colder air?
and this has been said before but the volume of air blowing out really sucks

[dcains]

R12 or R152a will surely provide more cooling, but the system will have to be flushed and a new drier installed, too. IMO, well worth it. Might have trouble finding a shop to install an alternative refrigerant, though, even with R152a being totally legal.

You might also consider upgrading the condensor fan, but honestly, I don't know what sort of volume the E12 fan provides. The OEM fan on my E24 is almost good enough, but I'm planning an upgrade on it, either from an E39 or aftermarket. The condensor is what pulls the heat out of the system, so that should always be a priority, with a PF condensor being only the first step.

Why not tint the windows? 3M makes a tint that will reject 97% IR and provide 90%+ visible light transmission. You can even use it on your windshield and the cops won't notice. My 350Z also has a lot of glass relative to the cabin size, and I waited until I'd had the car for 2 years before tinting the glass. Initially, the automatic a/c fan was pushing at max volume almost all the time, but after the tint it's almost at a whisper. I just bought the typical $200 ceramic tint for the Z, and it's got 35% light transmission. Dark, but not limo dark, and at the legal limit here in FL. I haven't tinted my 635 yet, but it's on the list. I like the dark tint on the Z, but the new 3M tint will offer better protection without the dark look. The only problem is the 3M tint is the expense, and I was quoted $700+ for the 635.. I was thinking maybe a 60% light transmission all-around, with the 90% on the windshield. Here's the stuff I'm talking about:

http://www.3m.com/3M/en_US/company-u...2716668&rt=rud

As for the cabin fan, yeah, that's a weak spot, and again, I don't know if your E12 is the same as my E24. I trimmed back the plywood inside the console, and it improved airflow significantly:

Before:



After:



Some guys have put a grille in the carpet on either side, but I haven't found that to be necessary.

[tonym427]

I have i think 30% huper optic ceramic and it works great. The car was driveable up to sub-90 degree days. In addition I installed a new Spal fan which pushes a lot of air through the condenser and I think is a must have. Its the cheapest upgrade at 70 bucks. My airflow in the cabin isn't huge due to the restrictions, but It sure is cold, around 40 degrees on R134.

[n2bimmer]

Thanks Dean & Tony, the shop i work with does have r12, he's a old school kind of guy and repairs radiators as well. .

I have replaced just about everything. So the PF condenser is new, new Spal fan, new lines, new drier, new expansion valve etc.
I believe the cabinet blower motor is the same for the e12.
When you removed that plywood how did you cover the carpet back over?

As far as tint goes, my glass/windows came with factory tinted glass, almost like a brown/gold, so i don't want to cover that up, also i like showing off my interior .

Thanks again..

[dm635]

I have opened up a hole in the plywood for my cabin AC fan. Only the drivers side so far, got to get the other side. I did a circle and also need to put a grill over the round hole . I agree that it has to help with air flow. For the condenser fan I added one from an E31. Whether that helped or not I don't know. But it definitely has more blades and the blades are curved. Even though I do have air flow through the center vents the 2 flaps that are supposed to open with AC do not open up. On my son's 6 you can hear the flaps open activating the AC. Can't hear it on mine. So I popped out a center vent to slide a mirror on a stick back there to watch the flaps on mine. They do not open like they do on DJ's 6. But there is still air flow. The only way to get to the flaps is to pull out the AC box.

[Mason Jones]

FWIW, I replaced the AC blower motor, fixed the vent flap above the evaporator, fixed the fan speed control, took the evaporator out and cleaned it (the fins were pretty clean already, like it had hardly been used) and put the vents all back together without the surround so I could check the ducts for air leaks and seal them with metal tape. After all that the airflow is just not that great. And that's before putting the surround back on so nothing is blocking the AC blower fan.

[dcains]

Thanks Dean & Tony, the shop i work with does have r12, he's a old school kind of guy and repairs radiators as well. .

I have replaced just about everything. So the PF condenser is new, new Spal fan, new lines, new drier, new expansion valve etc.
I believe the cabinet blower motor is the same for the e12.
When you removed that plywood how did you cover the carpet back over?

As far as tint goes, my glass/windows came with factory tinted glass, almost like a brown/gold, so i don't want to cover that up, also i like showing off my interior .

Thanks again..

The carpet on the console sides looks as it always did, but it's spaced out a few inches from the fan intakes, so it allows much more airflow. If you get the 90% 3M Crystalline film, it won't change the color or darkness of the glass by any appreciable amount. As I mentioned, you can even cheat and use it on the entire windshield, which is illegal almost everywhere, but the cops can't detect it. So, while it blocks ~97% of the IR (heat), it only blocks 10% of the visible light. Even without the a/c considerations, I want the tint to protect my new dash and leather.

[hakeem43020]

I decided to replace my aux fan. AC gets low 40s when cool but OEM fan doesn't really pull enough air to cool the car in hot temps(high 80s).

I bough a 16 inch spal fan instead of the 14 inch fan everyone else goes with and I can confirm that it does fit. It has 30% more CFM than the 14 inch spal version(1300 CFM vs 1000CFM) and I wouldn't be surprised if its double what the OEM did.
IMG_4686.jpgIMG_4687.jpg
It was very easy to mount and wire up. I still need to vacuum and recharge then I'll be good. I'm almost 100% sure this was my issue.

I also figured out how to adjust the valve. Screwing it counter-clockwise increase refrigerant flow to the pump. To avoid adjusting after charging I would advise to Just unscrew it all the way then charge. I'll report back after I recharge my system.

[n2bimmer]

The carpet on the console sides looks as it always did, but it's spaced out a few inches from the fan intakes, so it allows much more airflow. If you get the 90% 3M Crystalline film, it won't change the color or darkness of the glass by any appreciable amount. As I mentioned, you can even cheat and use it on the entire windshield, which is illegal almost everywhere, but the cops can't detect it. So, while it blocks ~97% of the IR (heat), it only blocks 10% of the visible light. Even without the a/c considerations, I want the tint to protect my new dash and leather.

Thank you, i will look into the 3M.


Over the weekend i had my A/C running, after 20 minutes the compressor started to intermittently groan, almost pulsating groaning. Its new from Ebay, is it maybe low on oil?

- - - Updated - - -

Regarding the fan ^^^ my mechanic accidentally wired the fan wrong, air was blowing away from the condenser instead of onto the condenser. The Freon pressure was crazy high. After my A/C guy figured it out the issue was resolved.

[hakeem43020]

Installed new aux fan. Replaced orings. Now both the low and high side readings are too high and keep rising. Hopefully I can figure that out by this evening. Not sure why :/

[n2bimmer]

Installed new aux fan. Replaced orings. Now both the low and high side readings are too high and keep rising. Hopefully I can figure that out by this evening. Not sure why :/

Is the fan blowing the right direction?

[hakeem43020]

Is the fan blowing the right direction?

What direction is the right direction? The fan should spin clockwise right?

i checked. Fan spins counter clockwise. Good call.

[n2bimmer]

What direction is the right direction? The fan should spin clockwise right?

i checked. Fan spins counter clockwise. Good call.

it should blow towards the condenser. I had mine wired opposite and my pressure was crazy high

[dcains]

Some fans are designated as a "puller" or "pusher", and even though you can reverse the polarity of the wiring, they lose efficiency when operated in the opposite way. Others are fully reversible, so you have to follow the manufacturer's instructions.

[n2bimmer]

Some fans are designated as a "puller" or "pusher", and even though you can reverse the polarity of the wiring, they lose efficiency when operated in the opposite way. Others are fully reversible, so you have to follow the manufacturer's instructions.

Thanks for the clarification.

[hakeem43020]

I almost have everything figured out but it Turns out luck isn't on my side and I have a very small leak. I had this leak before the conversion but I just assumed that replacing all the hoses/orings it'd be gone. It pulls down to -30 when I vacuum but doesn't hold the vacuum for longer than 10 minutes or 15 minutes. All hoses and orings were replaced and I did he soap water test but found nothing. Pulled out he evaporator and did the water and bubble test found nothing. I'm sure I'll find it eventually but no luck so far.

[88m53453]

check the schrader valves

[hakeem43020]

check the schrader valves

Thanks.

It's been a while. I had my system apart and decided to keep messing with it while it's out.

Found one of the big leaks that I had. Tried pressurizing the system but still had a leak. The metal line under the car that attaches to the drier also keeps leaking.
IMG_4800.jpg

Could be because I need to replace the drier since the system is left open. I have a new drier to install but want to be sure before I replace it or if that's a possibility.

[88m53453]

replace the seal and try again. Hose may be leaking, but it appears to be a seal issue

[jeffcfp1]

Anyone know part number (if available) for the line from compressor to condenser that has the accordion like aluminum heat shield over the line? Not able to id off of real oem diagram. Also, anyone know if that stuff can be sourced? Anything similar available?

[hakeem43020]

Anyone know part number (if available) for the line from compressor to condenser that has the accordion like aluminum heat shield over the line? Not able to id off of real oem diagram. Also, anyone know if that stuff can be sourced? Anything similar available?

Not sure about the part number but I do recall the line you're mentioning and should have it laying around with all the original hoses I removed if interested.

Also forgot to update. Thanks everyone for your help. I found the leak. The leak was on the voltage regulator. This part is only on the later e24s with the rear AC.
Attachment 606920
The rubber diaphragm has a pin hole leak in it. I applied some glue over it and I was all good to go. This is a new one so I have no idea how it managed to get damaged.

I also fixed the insuffient airflow through the middle vents(above the radio). I assumed that was how the car was made but found the issue has to do with the flaps on top of the evaporator box. When I took mine out it was very stiff and only opened half way forcefully.

I had to remove my flaps anyways since one the tabs of my doors were broken.
Attachment 606922
Attachment 606921
I welded(dremeled) a piece of plastic in place of the broken tab and got the door to fit snug and work as intended.

The flaps should blow and fall freely since its the air from the evaporator box that blows it open. To test it hold it above your head and blow up(be sure to give it a good cleaning before doing so). When I did this the flaps only opened half way hence only allowing little air to get by.

The flaps were rubbing on the side of the case preventing it from opening freely. I got some sandpaper and rubbed against the side of the case and the problem was solved.

I put my system back and charged it up and the vents above the radio now blow 90% of the air that the top one does. I now use these vents instead of the top ones since I can position them to blow on me rather than just cool the cabin.

I am still undercharged but I get 50 rear and 60 in the front but using the vents above the radio makes it a lot more bearable since the air is pointed on me.

I knew nothing about ACs or cars before I started this a year ago and spent most of my time learning and fixing my POs shortcomings. Thank you all for your help. Just a few more adjustments and I'll be done. Hopefully I won't have to mess with the AC again and if needs be I now know how to pull a wrench or two thanks to you guy

[jeffcfp1]

Yes, that would be helpful thank you. Glad you figured out your issues. This is a great thread but its terribly long. Wondering if several of us who have been through this should make a condensed thread of what they did with their system repair/upgrade and what they ran into. On this note, I also discovered the flapper issue and similarly had a tab busted off. For my repair, I cut a 1" long slot replaced with a cut off finish nail with a rounded nail head. Epoxied it in there with a small piece of a plastic bottle on each side to keep it intact with the potential pressure of popping it in. Also made a clip to hold the flappers from falling out of the groove, similar to what another owner did.\\

[tonym427]

Goodluck Hakeem!

[hakeem43020]

Goodluck Hakeem!

Thanks . Looking forward to the journey.

Yes, that would be helpful thank you. Glad you figured out your issues. This is a great thread but its terribly long. Wondering if several of us who have been through this should make a condensed thread of what they did with their system repair/upgrade and what they ran into. On this note, I also discovered the flapper issue and similarly had a tab busted off. For my repair, I cut a 1" long slot replaced with a cut off finish nail with a rounded nail head. Epoxied it in there with a small piece of a plastic bottle on each side to keep it intact with the potential pressure of popping it in. Also made a clip to hold the flappers from falling out of the groove, similar to what another owner did.\\

I found some of my AC lines. Not sure which one it is tho.
IMG_5239.jpg
Is it one of these?

I just realized this thread has 550 replies so yeah a condensed thread sounds good. I will start gathering info. Would you guys recommend updating my first post to show all the info or to just make a new thread?