A/C installation from scratch

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Robert Bondi
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Location: Austin, TX

A/C installation from scratch

Post by Robert Bondi »

I'm curious if anyone's done this before? Not repairing the A/C, but installing a system in a car that has none.....
I'm moving this project up on my Euro restoration car (77 528) because the car is otherwise generally unusable in my Texas climate.
I'm dividing my installation into three stages as my restoration is being done one major project at a time with some driving
in between.

Stage 1 (in progress): Switch to U.S. center console and install the blower box with a new fan. I call it U.S. as the donor car is for these parts - clearly the center console front and side panels are different for A/C cars. Even the extra fan will help before A/C is actually in. As I just had all the carpet out, I took the time to drill three new holes for later: condensate drain and the hi-side/low-side lines behind the glove box to the engine bay. Fortunately, I was able to precisely place these using measurements from my 530i. I'm cleaning up a donor blower box from a 79 E24 (E28 box also interchangeable, or at least from 84 528e). Latest headache here is discovering the need for peripheral parts, notably the base plate and the "covering piece" which is duct work.

https://www.realoem.com/bmw/enUS/showpa ... Id=64_0361

The base plate is shared with E28 and E24, so I can probably locate used. I expect a bit of fabrication need to close the gap for the covering piece.

Stage 2: A/C components in the interior, namely the evaporator and expansion valve. I have these new for the E28 and will be going that route of aluminum lines and o-rings. I'm probably also buying a bender for aluminum tubing.

Stage 3: Everything in the engine bay. Relatively easier for me since I did all this in converting my 530i to R134a...There's also
more room out there to customize and I can leverage various A/C kits and parts from other M30 cars. I already got the compressor stuff here since it's direct application for us with that nice bracket from our E28 friends: https://www.acsolutions.co/

There's a little bit of light wiring to navigate in all this as well.

I'll drop some pictures later.

Robert
Robert
77 530i
77 Euro 528
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Mike W.
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Re: A/C installation from scratch

Post by Mike W. »

I did it on a Bavaria long ago. Pretty straightforward except I neglected to do the evaporator drain hole. A few weeks after installation I heard this sound of water hitting a fan. Then soon I got some splashing up on my feet. Ooops. Not wanting to R and R the whole thing I improvised, which worked well for the next 100K or so until it was rear ended and totaled. I should say the improvised drain worked well, the Bav A/C as weak even after I replaced the old square York compressor with a E12 era swashplate one, it had a smaller blower and housing than E12s.

It's definitely doable. A bit of a challenge drilling the holes in the firewall for the lines, but again, doable. I may have that base mounting plate if it's the same as E28s, shoot me your email and I'll send a pic off.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
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Robert Bondi
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Location: Austin, TX

Re: A/C installation from scratch

Post by Robert Bondi »

Hi Mike,
PM sent. Thanks for sharing...that's encouraging. My hole saws went through the firewall surpisingly easy and I was working from the inside. Deciding exactly where to drill them was a bit of worry...

Robert

Mike W. wrote: Sat Feb 17, 2024 12:42 pm I did it on a Bavaria long ago. Pretty straightforward except I neglected to do the evaporator drain hole. A few weeks after installation I heard this sound of water hitting a fan. Then soon I got some splashing up on my feet. Ooops. Not wanting to R and R the whole thing I improvised, which worked well for the next 100K or so until it was rear ended and totaled. I should say the improvised drain worked well, the Bav A/C as weak even after I replaced the old square York compressor with a E12 era swashplate one, it had a smaller blower and housing than E12s.

It's definitely doable. A bit of a challenge drilling the holes in the firewall for the lines, but again, doable. I may have that base mounting plate if it's the same as E28s, shoot me your email and I'll send a pic off.
Robert
77 530i
77 Euro 528
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Robert Bondi
Posts: 371
Joined: Sun Jan 11, 2009 12:33 am
Location: Austin, TX

Re: A/C installation from scratch

Post by Robert Bondi »

Some picture updates...

I scored the base plate for the evaporator box. It supposedly from an 84 528e. One problem solved. You can also see the
condensate drain in the center.

Image

Here's the duct work blank plate off my non-AC car. Presumably, this is just removed and the "covering piece" is swapped
in to take the output of the evaporator blower box. I expect I'll be creating something out of plastic and flexible duct work.
Surprisingly, this plate is just held in by 3 of those Christmas tree type nylon fasteners so common on modern cars. Fortunately, the E12
has very few of these.

Image
Image
Robert
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Re: A/C installation from scratch

Post by 0257 »

Have not tried to install a complete system on an e12, but I did install an ICE Air kit on my 2002tii, which never had a/c before I bought it. You have already identified the scariest part of the job, which is drilling through the firewall. Measure again and again for about a month, then drill once! Obviously your ac car can give you some guidance as to where to put those holes, but it’s still hair-raising. Watch out for brake lines and wires!

Finding all the parts is the next most daunting task, which is why i bought the available kit. Did not have the courage of my convictions. Might do it piecemail if I had it to do over again. Good luck with that part.

In fat, as you know, that’s what I’m doing now on my 528i. Have the acsolutions bracket and a Sanden, and have located a 17x19 parallel flow condensor at Vintage Air just up the road from you which I think will fit the apron opening just about right. Still searching for the right drier.

Also thinking about how to upgrade the anemic blower and evaporator. Spent a good part of today getting the evaporator box exposed for removal and will pluck it tomorrow. Looking at the blower fan, i’m not sure it’s not even smaller than the e9 fan. That said, there seems to be enough room under the dash for a bigger unit, like your e28 box. Also, it looks like it may be possible to put an e28 fan in the e12 box. I have what I think is an e28 box and will try to test fit it. Has a much bigger hamster wheels than my e12 unit; also, the info I’m getting from various vendors indicates the bigger e28 fan may fit in the e12 box. I know you have mix and match parts as well, and may be trying similar. So, much experimentation coming up in the next weeks. Will follow this thread with interest. Good luck to us!
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