[s-cars] High coolant pressure and heater valve

[Vincent Frégeac]

I'll try that, just to be sure. The head gasket have been replaced a year
ago but by a mech, not me, and I'm always a bit nervous when someone else
have put his hand under the hood.
 
Thanks for the tip.
 
 
 
Vincent.
  _____  

De : Djdawson2 at aol.com [mailto:Djdawson2 at aol.com] 
Envoyé : 16 janvier 2006 22:36
À : vfregeac at sympatico.ca; josh at spiny.com
Cc : s-car-list at audifans.com
Objet : Re: [s-cars] High coolant pressure and heater valve


In a message dated 1/16/2006 7:47:20 PM Mountain Standard Time,
vfregeac at sympatico.ca writes:

That's what surprise me. It's not to high a pressure, the kind you can hold
with your thumb on bicycle pump. How can it make a hose pop out when it's
holding on a 3/4 inch tube with a tight collar. Am I right to suspect a much
higher pressure in my coolant system?


I would suggest that what Varon has told you is accurate.  I would also
suggest that you try a simple test... starting with a cold engine:
1) loosen your overflow tank cap, enough to relieve pressure as it builds
2) warm the engine for just a few minutes... enough that you would be
comfortable doing a quick high boost run
3) run the car several times to max boost, 1st to 2nd twice should do fine.
 
Do this quickly, before the car reaches full operating temp.  Then, pop the
hood, and see if you've blown any coolant past the loosened cap.  If you
have, you likely have a blown headgasket, allowing excessive pressure to
enter the cooling system.
 
When you've blown the headgasket in such a fashion, the usual first signs
are failed cooling system components... a radiator, a hose, the aux cooling
pump, etc...   These will be repeated failures... fix one, and get another
one.  When this is happening, it typically indicates pressure spikes well in
excess of the system's design.
 
This possibility is worth eliminating right off the bat, before you
potentially blow apart a bunch of expensive cooling system parts.
Good luck,
Dave