[V6-12v] V6-12v Digest, Vol 72, Issue 3

[Tom Christiansen]

Folks,

The heater core project is an evil one, but it is doable for a DIY person
who pays attention to detail. I believe I wrote up a procedure for doing
this a while back (probably May 2005 or so).

I took a 3-day weekend to do it.

Aside from the nut behind the radio holding the duct work together, I don't
recall any downright gotchas. That nut does need to be removed or you'll
spend two hours trying to get the dash out before realizing that if you just
take that nut out the dash will come out in about 5 minutes.
On the heater box there is an air valve. I seem to recall it controlling the
recirculation/direct air flap. $10 says you'll bust that valve getting the
heater box out. Either get a replacement up front, or do what I did and
epoxy it together after you bust it.

In addition to the heater core, replace the foam around the flaps directing
the air. It's probably pretty rotten by now. I seem to recall AutohausAZ
having the foam kit...

~ Tom


On Wed, Apr 28, 2010 at 1:20 PM, Tom Leppke-Hennig <printhead at usinternet.com
> wrote:

>
> >
> > Message: 4
> > Date: Wed, 28 Apr 2010 14:25:58 -0400
> > From: Kent McLean <kentmclean at comcast.net>
> > Subject: Re: [V6-12v] FW: Window Fogging
> > To: v6-12v at audifans.com
> > Message-ID: <4BD87DB6.70502 at comcast.net>
> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed
> >
> > Casimiro Izquierdo wrote:
> >>
> >> ----Forwarded Message----
> >> From: caig01 at yahoo.com
> >> To: caig01 at yahoo.com
> >> Sent: Wed Apr 28th, 2010 1:41 PM EDT
> >> Subject: Window Fogging
> >>
> >> I am having a problem with my 1995 Audi 90S.  When the car warms up
> >> there is
> >> a cloud of "water vapour" that rises tthough the vents and fogs the
> >> windshield and the driver side window.  This "vapour cloud" leaves a
> >> film on
> >> the glass surface that is very difficult to clean; it smears and Windex
> >> clears it to some extent.  It does not seem to be burning oil, which the
> >> car, but it seems to be coolant.  It does not smell much like coolant,
> >> but
> >> the film suggests antifreeze deposit.
> >>
> >> - What can be done to either prevent this from happening?
> >> - How can I completely close the vents?  I do not care about A/C or
> >> heating,
> >> neither work.
> >>
> >> Any suggestions will be appreciated.
> >
> > It sounds like the heater core is leaking. That fog on the windshield
> > is probably from the coolant drying on the it.
> >
> > If you truly do not need the heat, you can bypass the leaking core.
> > There are two heater hoses (about 3/4" or 2cm or so) going from the
> > engine through the fire wall to the heater core. Follow those two
> > hoses back to the source on the engine block, remove them, and replace
> > them with a shorter (1 foot or 30cm or so) piece of heater hose, in
> > a U-shape, going from one outlet to the other (or rather, going from
> > the outlet to the inlet; but you don't have to know which is which).
> > This will take the heater core out of the loop. It might still fog
> > a little until the water in the heater core has evaporated, but it
> > should "fix" the problem.
> >
> > If you *do* need heat, you'll have to replace the heater core. This
> > is a fairly inexpensive part (about US$100), but is labor intensive
> > to replace (up to 9 hours, depending on who you ask). You can do it
> > yourself; direction are on-line and in the archives.
> >
> > --
> > Kent McLean
> > 1990 V8 w/5-speed and other mods
> > 1991 200 TQA #3, with mods
> > 1999 A4 Avant, V6 Tiptronic
> > gone: '91 200 TQA x2, '94 100 S Avant, '89 200 TQ "Bad Puppy"
> >
>
> Casimiro Izquierd,
>
> I too have heard the siren-song of 'just bypass the heater core' (on a
> different car) and I can tell you that in anything but the most mild
> weather, it is an absolute pain in the arss. It is surprising how often a
> little bit of heat needs to be added to the ventilation air. Without it,
> it makes dealing with rain and damp air nearly impossible. My opinion.
>
> The bad news: The heater core on the B4 series is a big project (probably
> a big project on all audis). However, once you get into it, it's very
> do-able.
>
> Tom LH
> 1995 90>
>
>
> _______________________________________________
> V6-12v mailing list
> V6-12v at audifans.com
> http://www.audifans.com/mailman/listinfo/v6-12v
>