Air conditioning back in

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xavier
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Post Tue Feb 11, 2020 9:29 am

A few years back a kind soul(son) took the air conditioning out of my 1984 323. Apparently I didn’t need it. He put all the parts in a big box. I have had the car repainted and I am in the process of recommissioning it. Can the old system be put back in an regassed?
MikeBM299
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Post Tue Feb 11, 2020 12:03 pm

If you are interested in selling the whole kit i would be interested.
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Tzantushka
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Post Wed Feb 12, 2020 6:17 am

Technically possible.
But if you have all the parts out, why not complete the conversion to R134a?

Converting from R12 to R134a requires a few changes as the refrigerants and associated oils have differing chemical/thermal & physical properties.

Most of the hard pipes can be flushed out and re-used (ensure you have compatible o-rings)
Best to use a new receiver drier.
Also best to use R134a compatible TX (thermal expansion) valve & pressure switch.
If your compressor is out of the car, that may need a rebuild.

Assuming you're in the UK - that might be enough to get you comfortable.
But for hotter climates (e.g. Australia) best to change the condenser to a more efficient parallel flow unit.

Appears I have R12 components with R134a regas and it's 'OK' not icy cold - but 'OK'.
Will see how long the system lasts
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xavier
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Post Wed Feb 12, 2020 10:31 am

I am in Western Australia. It gets @#$& hot. So you are using the original compressor? I thought about trying to fit a Toyota system. They are by far the best I have come across.
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Tzantushka
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Post Thu Feb 13, 2020 10:18 am

Ah. Surprised you lasted this long without A/C.

Yes, I'm using the original (Bosch) compressor.
But unlike your situation, it's always been in the car and run occasional so the seals are good.
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martauto
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Post Sat Feb 15, 2020 3:10 pm

What the hell is "AC "
Storm Dennis is here right now and a massive 12 deg C for Feb. winkeye winkeye winkeye winkeye winkeye winkeye winkeye

Mart.
Only the E46 cab left now.
Just got too old.
HenryM3
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Post Tue Mar 10, 2020 7:50 pm

A few years ago I retrofitted a/c and bmw at the time sold a kit to convert from r12 to 134a
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flybynite
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Post Wed Mar 11, 2020 7:43 am

The conversion kit is now NLA from BMW (at least UK side) although most bits are available separately and seals/o-rings are can be had from a specialist.

There is the discussion as to whether the original Hella/Behr tube and fin condenser will work as well with R134a as a parallel flow condenser like the Nissens.

Curoiusly the new Hella/Behr condenser I have here is stamped for both R12 and R134

Curious to know what the aircon has run like on an E30 with R134 and original condenser?
HenryM3
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Post Wed Mar 11, 2020 12:14 pm

What can I say, in all honesty mine is not great. It works as it should but not as cold as a more modern car. Can’t find any faults, it doesn’t leak, fan runs when on. I have tried to get over being picky as it makes the car way more comfortable with it than without.
Edit Having thought about it, mine is a bit of a mix and match in that 80% is E30 and the rest s50 b32. Don’t know if that contributes towards the slight imperfection.
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flybynite
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Post Wed Mar 11, 2020 5:38 pm

HenryM3 wrote:
Wed Mar 11, 2020 12:14 pm
What can I say, in all honesty mine is not great. It works as it should but not as cold as a more modern car. Can’t find any faults, it doesn’t leak, fan runs when on. I have tried to get over being picky as it makes the car way more comfortable with it than without.
Edit Having thought about it, mine is a bit of a mix and match in that 80% is E30 and the rest s50 b32. Don’t know if that contributes towards the slight imperfection.
That is quite interesting and backs up some of what I read when using R134a with the existing systems.

If you ever get cause to replace the condenser it may be worth trying a parallel flow one like the Nissens instead of the fin and tube one.

An original one will be going on the chromie because the modern alluminium parallel flow one looks out of place, But I have a new Nissens waiting to go on the Facelift when I get to it.
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Post Wed Mar 11, 2020 8:27 pm

I remember when I was an apprentice all the older mechanics used to say the R12 was always better than the new R134a, much colder. Its worth asking around as some places still have R12 canisters in corners/under benches etc etc
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Post Wed Mar 11, 2020 11:33 pm

Yea, I heard that to, what would be the result of putting r12 into a r134a system. If I could find some.
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Post Thu Mar 12, 2020 12:37 am

I went from R12 to R134 and couldn't tell any difference, they were both quite poor. It blows cold but not cold. My main problem with using it is the noticeable drop in engine power and an idle speed of about 1000rpm.
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HenryM3
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Post Thu Mar 12, 2020 12:57 pm

I don’t suffer any idle problems with it. I just need to stop whinging, it’s better than not having it. Like the cruise control, not as good as modern day stuff but great to have and working on a 30 year old car.
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Post Thu Mar 12, 2020 12:58 pm

I'm not saying the raised idle is a problem, it's to be expected, it's just annoying.
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Brianmoooore
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Post Thu Mar 12, 2020 2:16 pm

The performance of a refrigerant depends on its boiling point and latent heat of vaporisation. Crunch the numbers and R134 will lose about 20% of the performance of the same system filled with R12.
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Brianmoooore
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Post Thu Mar 12, 2020 2:18 pm

Cloggy Saint wrote:
Thu Mar 12, 2020 12:58 pm
I'm not saying the raised idle is a problem, it's to be expected, it's just annoying.
Easily dealt with. Just disconnect the wire from the aircon switch to the engine ECU. Downside is that the engine may stall if the aircon kicks in while the engine is at idle. The idle speed control can't respond quickly enough to deal with the sudden engine load.
HenryM3
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Post Thu Mar 12, 2020 4:06 pm

I think I’ll leave the number crunching to you Brian, 20% is quite substantial though. Are the newer a/c systems designed different to compensate or can some different or additional bits be added to improve our old systems.
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Brianmoooore
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Post Thu Mar 12, 2020 7:00 pm

Air con system can be designed to turn the inside of the car into a mobile domestic freezer if required. There's no problem designing the 20% back in when specifying the bits from scratch.
Larger/more efficient condenser would get back most of the 20%.
HenryM3
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Post Thu Mar 12, 2020 7:37 pm

Thanks, I’ll try and remember that if I ever have to replace it
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Post Thu Mar 12, 2020 7:50 pm

HenryM3 wrote:
Thu Mar 12, 2020 12:57 pm
I don’t suffer any idle problems with it. I just need to stop whinging, it’s better than not having it. Like the cruise control, not as good as modern day stuff but great to have and working on a 30 year old car.
What is the difference with the cruise control on moderns?

The only one I notice is that on moderns you have to turn it on before you activate it.

Ben
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flybynite
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Post Thu Mar 12, 2020 7:50 pm

As I mentioned above, Nissens do a parallel flow condenser specifically for the E30 running on R134a. (not that expensive from Autodoc on a good discount day)

Have not used it in anger but from what I read it works better than a serpentine or tube and fin, although an aircon specialist near me claim they can make a traditional looking Behr/Hella work well with R134a

What compressor are you using on the S50? e30 or E36? I have looked at the differences between E30 and E46 compressors for one of mine but can't remember what I had on the E36 M3
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flybynite
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Post Thu Mar 12, 2020 7:55 pm

BenHar wrote:
Thu Mar 12, 2020 7:50 pm
What is the difference with the cruise control on moderns?
The one on my daily (getting on for 5 years old now) keeps distance (adjusted for speed) to the car in front all the way down to standstill. (it is an auto)

One of the few actually useful gadgets I have had on a car in recent times
HenryM3
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Post Thu Mar 12, 2020 8:44 pm

I have the e36 compressor fitted. Had to mod the hose connections to and from the compressor. It’s not as neat as I would like but can’t find anyone to make a decent hose preferably braided. While I’m on here and people are reading, any bright ideas how to restore/brighten up the white lettering on the stalk?
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flybynite
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Post Thu Mar 12, 2020 9:26 pm

HenryM3 wrote:
Thu Mar 12, 2020 8:44 pm
While I’m on here and people are reading, any bright ideas how to restore/brighten up the white lettering on the stalk?
Mo Faraz has replacement lettering (transfers) not the cheapest bit of a faff to get it right but good results when you do

https://mofaraz.com
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BenHar
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Post Fri Mar 13, 2020 2:03 pm

flybynite wrote:
Thu Mar 12, 2020 7:55 pm
BenHar wrote:
Thu Mar 12, 2020 7:50 pm
What is the difference with the cruise control on moderns?
The one on my daily (getting on for 5 years old now) keeps distance (adjusted for speed) to the car in front all the way down to standstill. (it is an auto)

One of the few actually useful gadgets I have had on a car in recent times
That's not really cruise control.

It sounds bloody awful too. Sounds as though you just want a chauffeur.

Ben
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flybynite
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Post Fri Mar 13, 2020 2:20 pm

BenHar wrote:
Fri Mar 13, 2020 2:03 pm
That's not really cruise control.
It sounds bloody awful too. Sounds as though you just want a chauffeur.
Ben
"Adaptive Cruise Control" is what it is and it holds a speed like any other cruise control.

Unlike every other cruise control it won't run into the back of a slower car/van/truck/tractor in front, :banghead: simply slows down to match until you overtake. No switching it on and off, on and off, on and off :mad:

Bloody marvellous invention if you ask me. :thumb:

Had normal cruise control on the E36 Evo and with nothing but a 210 plate LSD to control it the thing was quite brutal engaging and disengaging and could go sideways when you re-engaged it from a slower speed 8O
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Post Fri Mar 13, 2020 7:08 pm

Heres a pair of compressor hoses I modded to ft an E36 compressor, they started out new
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HenryM3
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Post Fri Mar 13, 2020 8:04 pm

That top hose that goes up the strut tower is way neater than mine. I’m jealous.