To Convert or Not to Convert...

[Wes F]

Hey all. Just want some advice on the 'ol A/C issue. Brought my car in to a shop today to have the A/C checked. It worked fine for a few years after I bought the car, and then started slowly to blow warm. It's the original R12 system. I took it to one of those A/C shops (probably first mistake) just to have it charged, course the f*ckers said I needed to replace the whole system, to the tune of $3800 to fix - yeah, whatever. So anyway it blew ice cold for about a month or two and then started blowing warm again - so obvious leak.

Anyways, I wanted to know exactly where the hell it was leaking from - not the ******** canned, "well it's leaking from your compressor, condensor, evaporator and lines. Yeah, we really should replace everything. But our work is guaranteed." Not ****, if every freaken component is new, it damn well should work!

So I found this shop (that knows Bimmers) that tests R12 systems - it's amazing how many shops nowadays won't even touch R12. They just immediately convert it over to 134 and THEN diagnose what the problem actually is. Most of the places I had called said this.

So the guy was cool and allowed me to watch. He had that sniffer gauge to detect leaking freon, and sure enough that thing zinged like a mother when he passed it by the low pressure line where it's clamped down kinda near the drier. So I need that. Plus, when he went under the dash, it beeped a little bit by the fittings where the evaporator is. He said he couldn't tell for sure if it was the fittings or expansion valve or evaporator without ripping the dash apart, but said might as well replace them and be done with it.

So I'm left with replace low pressure hose, some o-rings, expansion valve, and evaporator (as well as drier of course), and should be good to go. Should I dick with going ahead and converting the system while I'm at it? I'd rather honestly keep it R12 since it cools a hell of a lot better than R134a (it gets hot as **** here in Hawaii). The only thing is everyone I have called charges $80/pound, so that's minimum $320 in gas alone. But if that could last another 5-10 years of arctic a/c then it's worth it to me...I think I can tackle the work myself, but I don't have gauges or a vacuum pump so I'll have to bring it in to have it evacuated and recharged...any thoughts on what's the best course of action? Thanks a lot for your input.

[wingman]

Sorry to hijack but with your sig pic if you have the pilot can I be your 'wingman' and have the co-pilot???:D

[Wes F]

Sorry to hijack but with your sig pic if you have the pilot can I be your 'wingman' and have the co-pilot???:D

Yep, the left-seater's mine. Always helps to have a wingman though, go ahead and consider the right-seater yours. ;)

[Mr Project]

The replacement of the parts is not very difficult IMO. I converted my 535i, and just converted my 535iT as well, though I haven't gotten it charged up yet.

Getting under the dash and replacing the evaparator and expansion valve is similar to a microfilter change. Pull the glovebox and the inner cover, then there's another cover over the evap. core and valve/tubes. The one complicating factor is that you need to pull off the false bulkhead in the engine compartment to get at the bolt that holds the tubes that go into the expansion valve...you need to remove those tubes to slide the evap. core out.

Once you have it apart don't forget about new o-rings and I like to use a little nylog sealant/lube as well.

Frankly I'm still a fan of going the extra mile and converting to R134....the evap removal is probably the hardest part of the conversion, and what happens if you screw something up and the R12 leaks out again? That starts getting expensive REALLY quick.

[brosher]

Never worked with a sniffer before. One thing that is more acurate I have heard of to detect leaks is the put a dye in your system. Then you drive around for a couple days with the compresser running. When you come back they can take a black light to the system and find all the leaks. Sounds more accurate than a sniffer.

[Bill R.]

older cars with r12, its still readily available here and the price isn't that bad (plus i have a couple of 30 pounders from back when it was a couple of bucks a pound.) I have done a number of conversions to freeze 12 which all of the checkers auto parts here carry.

It works much better than the r134a conversions in my opinion and the freeze 12 is about 6.99 a 12 ounce can right now at checkers. Its completely compatible with r12 systems so you don't have to change out anything, no barrier hoses, same filter drier, same compressor etc. You can order the conversion kits online if needed and autozone now have refrigeration vacum pumps on their loaner tools at the bigger autozones, i'm not sure if checkers does.

Where i'm at the ambient is much higher than hawaii and freeze 12 works fine for most cars, unlike r134a. The dye check does not work better than a good sniffer, the main problem with a good sniffer like the tiff that i have is that its so sensitive that it will detect leaks as small as 4 ounces per year, so it goes off at the slightest leakage and you get a lot of false readings.





Hey all. Just want some advice on the 'ol A/C issue. Brought my car in to a shop today to have the A/C checked. It worked fine for a few years after I bought the car, and then started slowly to blow warm. It's the original R12 system. I took it to one of those A/C shops (probably first mistake) just to have it charged, course the f*ckers said I needed to replace the whole system, to the tune of $3800 to fix - yeah, whatever. So anyway it blew ice cold for about a month or two and then started blowing warm again - so obvious leak.

Anyways, I wanted to know exactly where the hell it was leaking from - not the ******** canned, "well it's leaking from your compressor, condensor, evaporator and lines. Yeah, we really should replace everything. But our work is guaranteed." Not ****, if every freaken component is new, it damn well should work!

So I found this shop (that knows Bimmers) that tests R12 systems - it's amazing how many shops nowadays won't even touch R12. They just immediately convert it over to 134 and THEN diagnose what the problem actually is. Most of the places I had called said this.

So the guy was cool and allowed me to watch. He had that sniffer gauge to detect leaking freon, and sure enough that thing zinged like a mother when he passed it by the low pressure line where it's clamped down kinda near the drier. So I need that. Plus, when he went under the dash, it beeped a little bit by the fittings where the evaporator is. He said he couldn't tell for sure if it was the fittings or expansion valve or evaporator without ripping the dash apart, but said might as well replace them and be done with it.

So I'm left with replace low pressure hose, some o-rings, expansion valve, and evaporator (as well as drier of course), and should be good to go. Should I dick with going ahead and converting the system while I'm at it? I'd rather honestly keep it R12 since it cools a hell of a lot better than R134a (it gets hot as **** here in Hawaii). The only thing is everyone I have called charges $80/pound, so that's minimum $320 in gas alone. But if that could last another 5-10 years of arctic a/c then it's worth it to me...I think I can tackle the work myself, but I don't have gauges or a vacuum pump so I'll have to bring it in to have it evacuated and recharged...any thoughts on what's the best course of action? Thanks a lot for your input.

[winfred]

i've converted many dozen e34/32s to 134 and it works pretty good when the system is in good shape (and our summers run upper 90s with high humidity) most of the time the leak under the dash is the o-rings on the valve but i always pull the evap out to check it for oily spots and clean the fuzz off, it only takes a minute or two extra to pull the evap if you are doing the valve, id say a quarter or less of these cars need evap's and if you need one get a real one the aftermarket units suck! depending on brand some won't even fit. i don't use alternative freons as i have r12 and r134 ac machines and can't recover it without contaminating my stock of freon

[Wes F]

Thanks a lot guys for the replies! So I think I might just try to keep it with the r12. Seems to be easier. Winfred that sounds about right that the leak under the dash is probably the fittings to the evap, and not he evap itself. I'll probably just change the expansion valve, o-rings, and that low pressure hose and be done with it. Hopefully that should take care of it.

Now I just gotta figure out how to get my hands on 4 1/2 pounds of freon without paying up the arse. Anyone in Hawaii here that knows a place? I was browsing the net and it seems even if I get an EPA license to buy the stuff myself most places won't even ship here - ground shipping only in the continental US...thanks again! You guys make this forum a gold mine of essential info!

[Blitzkrieg Bob]

And I live in Honolulu.

No problem cooling.

I like it, cause I can do the work myself.

[winfred]

heres where you can get that if you didn't know (http://www.macsw.org/certification.php)


if I get an EPA license to buy the stuff myself

[Wes F]

heres where you can get that if you didn't know (http://www.macsw.org/certification.php)

thanks winfred, I appreciate it.