RE: <E30> R134a???

["Fadeev, Alex" <Alex.Fadeev@xxxxxxxxxxxxxx>]

Folks, check the digest archives!!!
There is a R134 conversion related post showing up almost daily!

> Anyone convert an E30 to R134a? 
> It's 100degrees + high humidity (feels like 110) and my AC 
> gave up the ghost yesterday (coated my exhaust manifold with
> oil -- probably a hose or seal).

Or the high pressure switch let go...

> I was wundering how much cooling would be lost with R134a.   With R12 
> prices going way up (cost my $110 to have the system 'topped off' two
> years ago -- I hate to see what  a complete charge will cost).

Here is my reply to an earlier poster on E30 R134 conversion:
- --------------

	I've done R134a swaps on both my '89 and my wife's '90 E30s. Both
went well. Part came from http://www.allbmwparts.com/ for $100 which is the
same "factory conversion kit" BMW sells for $200. Looking at the parts they
should not cost more then $50 if you know what to procure.

> 1. Do I have to change the o-rings? 

No.

> 2. Would I have to remove the compressor to flush it?

Yes. From below.
 

- -----Original Message-----
From: Fadeev, Alex 
Sent: Monday, April 26, 1999 5:20 PM
To: 'bmwuucdigest@domain.elided'
Cc: 'BOBINYELM@domain.elided'; 'Alex_Angelopoulos@domain.elided'
Subject: Re: Subject: 325e A/C not working


> It started last year when his A/C unit started acting funny.  
> By funny I mean it would work (turn on), but only pump out
> semi-cold air. 

The classical symptom of a leak. Lower Freon pressure => less cooling.

> My father took it to a local shop where they proceeded to
> tell him that his A/C unit needed a recharge freon.  Now I
> know what you're thinking - freon is illegal.

Nope, it's legal. Just rather expensive. 

> Well they didn't fill it with freon, they used the new
> substance.  I just can't remember the name of it.  Now
> after a fairly tame winter here on the east coast of
> Canada, the old 3'ers A/C is acting even stranger. 
> It now works (the fan is on) but it now pumps out regular 
> air.  Not even a hint of cool air. It's like he doesn't
> even have the A/C switched on.

Not necessarily strange. Same symptoms like before, only at a latter stage
of cooling degradation. The Freon replacement has leaked out (probably
through the same leaky component that did not get replaced).
Whatever was causing the leak in the first place in the car never got fixed.
The shop just evacuated freon and charged the system with some substitute
(probably because you dad told them to use a substitute after he saw the
bill for 2 pounds of freon). 
If the substitute is R134a, then the shop would have also replaced:
- - compressor oil (and $350 compressor depending on the model)
- - pressure hoses between compressor and evaporator ($200 on pre-87 {89?}
E30's)
- - dryer (upstream from compressor). This one gets replaced whenever AC
system looses pressure
- - valve, since R134a equipment uses different valves
- - pressure switches. I believe R134a runs at higher pressure so the stock
Freon switch would open if left unattended.
- - the actual gas in the AC system (R134a). Most decent shops also put a
sticker on the passenger side strut tower (near the fill valve) identifying
the replacement substance.

Judging from your description, the shop either did not find the leak or did
not look for it. They also probably did not do R134a conversion or your dad
would have remembered the name of replacement substance after getting the
bill. Now the Freon substitute is gone as well. 

> Before he takes it in to the local stealer, I just wanted
> to tap the wisdom of this list to find out what some of the
> common things that can go wrong with this system.

My wife's E30 leaked Freon from the evaporator. 
Mine melted the high pressure switch last summer for no obvious reason.
I converted both cars to R134a for $100 parts (both post-89 E30s) and
another $100 labor each. R134a has been adequate in Dallas, TX summers (one
car untinted), although it seams to take longer to start cooling the
vehicle. Once it gets going, it cools as good as Freon. A year later
everything is still working.

> Maybe I can even look for these items myself?

Not unless you want to invest $$$$ into Freon sniffing equipment. 

Take the car to a reputable AC shop, identify the leak and then consider
converting to R134a. 
The conversion components cost me around $100 in aggregate from mail order
places. Figure 1.5-2 hours of labor to swap compressor oil, install new
valve/pressure switches and charge the system. Plus whatever time it takes
to identify the leak and replace the leaking component (hopefully some
O-ring). 

hope this helps,
alex

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