[Vwdiesel] A/C. Again (fwd)

[James Hansen]

I just caught up on your past note Shalyn...
Compressor will definitely be noisy if the system is overfull.  It will also
hammer if the oil is low and the pump is on it's last nickel.... so with an
old pump, I'd be tempted to change it if you suspect it... particularly if
you don't have the stuff to do it yourself and you'll nickle and dime
yourself to death trying different things getting a shop to vac and charge
it.  You say it's hammering really really bad, it's probably one step from
going down.  Hook up you gauges and see, but it's either really low with a
stuck low pressure cutoff, or really screwed. Really full usually just blows
a hose if the high pressure cutoff is not working or expansion valve is
plugged. As Loren said, an old refrigerator pump works well for a vac pump,
and you can make it recover by putting a fan and an old condenser on the
pump exhaust that terminates in a tank after the condenser. Vac pump and
gauges are a must to roll your own, but if you can't recover, it isn't
technically legal to just dump it to atmosphere to work on it here, dunno
about in the US. One of the reasons I got a reclaimer/recharge unit...
nickel and dime costs to get a mobile truck out to the farm are usually 500
bucks bare minimum, so it pays pretty quick.

So, if you're changing the compressor, change the receiver dryer too.
Dollars to doughnuts the dessicant bag in the dryer will pop immediately
after changing the compressor and plug the system, then it's clean, flush,
clean out the expansion valve, play some more etc. real pita.  Look up specs
on the oil volume and type, make sure the compressor either has oil or
doesn't (usually does when new).  I like the vac and hold overnight, then
revac the system method too.  I'll skip it if in a  hurry, but it pays off,
if you come back in the morning, and you don't have vacuum, there is for
sure a leak, find it.  It's only 15psi pressure fighting to get in, not like
a pressure test, but does help, and will dry the system out better if not
changing the receiver dryer can.
$60 is a good deal to remove and replace the freon.
-james

-----Original Message-----
From: vwdiesel-bounces at vwfans.com [mailto:vwdiesel-bounces at vwfans.com] On
Behalf Of Shalyn Shourds
Sent: May-15-13 10:28 PM
To: vwdiesel at vwfans.com
Subject: Re: [Vwdiesel] A/C. Again (fwd)

That's good to know.  Autohausaz is where I got my last compressor from. 
The unit that came off was a Sanden, the one that went on was a Behr.  I
don't know if it's equivalent or a Chinese clone (a different retailer tried
to sell me a "Pacific Rim" brand....).  As far as I know, the first one
lasted 11 Texas summers.  That's why I'm tempted to spend a bit more.  I
found a company listing a new Sanden Unit for $317.  Autohaus has their unit
on sale for $220.  I'm also a bit conflicted.  The car's got 325,000 mi and
the body and interior are pretty rough.  If the drivetrain weren't in such
good shape, I'd go cheap without a thought, get through a couple more years,
then buy another.  As it is, I tend to be rewarded for going for the best.  

I have a set of gauges.  I have neither a vacuum pump nor a compressor. 
Hard to believe I've made it this long without air, but I have.  Local shop
charges $60 to remove, vacuum, and replace the refrigerant, so that's what I
do.  Dad has all that stuff, but lives a ways off.  I'll see what I can do
about getting a system flush too.  This compressor sounds really really
bad.....

-Shalyn
_______________________________________________
Vwdiesel mailing list
Vwdiesel at vwfans.com
http://www.audifans.com/mailman/listinfo/vwdiesel