[V6-12v] Bizarre Cooling System Problem

[Wilfried Link]

Update to mystery below:

After replacing the heater-pipe-to-block O-ring (just
as I replaced it's coolant pipe neighbor earlier), and
over-tightening the upper radiator hose clamps, the
only leak that remains is a very slight crusting at
the upper-radiator-hose-to-coolant-tank connection.
System pressure test conducted by 2Bennett Audimotive
was normal, and their test for exhaust gas in the
coolant was negative, so head gasket, water pump,
radiator and thermostat all good. Seems as though the
new hose is not quite of the right size or
composition, and the wrecking yard motor had two
crusty rubber O-rings at 72000 miles. Odd, but not out
of the question. If the upper hose problem continues,
I'll buy one from a different supplier and replace it.
Thanks for the inputs all.
  
Wil
> 1995 A6 Avant
> Vacation Cruiser



On 29/5/05 4:48 pm, "Wilfried Link"
<wilfriedlink at yahoo.com> wrote:

> Here's a great brain teaser:
> 
> Cooling system functions perfectly but for small
leaks
> at four different hose connections and a moderate
one
> past the O-ring at the coolant pipe where it enters
> the block behind the thermostat. Engine is from a
> wrecking yard with 75,000 on it. Rest of car has
> 182,000. New upper radiator hose and said O-ring .
> Cooling system flushed. Heater works perfectly. Hose
> connections have been adressed by cleaning
> connections, tightening, loosening, you name it.
> Clamps are way tight, still leaking! O-ring
replaced,
> still leaking! Only thing I can think of is
> overpressure, but cap was swapped and tested (15
psi),
> no difference. Aaargh! Water pump was replaced two
> weeks ago by 2Bennett Audimotive after it stranded
me
> in mountains by gushing coolant out of the freeze
plug
> at a horrendous rate - which sounds like blown seal,
> right? Only old part that plays a role in this to my
> mind is the radiator. However, even in hot weather
> the system works perfectly -- oil and water temps
both
> happily normal. This car is to take us 3000 miles
into
> Canada and back in a few weeks, and at this rate
I'll
> spend more on Pentosin than gas!   Any clues out
> there? I'm about to put in a new AC compressor ($595
> A-Air Online Florida -- great manager, Keith-knows
our
> compressors very well), and just sank a ton into
this
> newer motor (2Bennett again), so I tire of
high-dollar
> fixes.
> Thanks in advance,
> 
> Wil
> 1995 A6 Avant
> Vacation Cruiser