[s-cars] High coolant pressure and heater valve

[Djdawson2 at aol.com]

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