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[email protected][_2_] trader4@optonline.net[_2_] is offline
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Default radiator caps, cooling system pressure

On Apr 21, 11:15*pm, wrote:
On Sun, 21 Apr 2013 18:50:29 -0700 (PDT), "





wrote:
On Apr 21, 6:11*pm, Tony Hwang wrote:
Ashton Crusher wrote:
I was thinking of putting a higher pressure cap on one of my cars to
increase the factor of safety against boiling. *Looking thru the web
for info on the likelihood of changing from 7 psi to 13 psi causing
leaks I found little on that issue but did find a couple references to
the pressures created by the water pump. *One site boasts of a 19 PSI,
$25 cap to get you thru your "hard driving".
http://www.mishimoto.com/mishimoto-h...tor-cap-13-bar.....
Thought I'd see if anyone else has heard of this. *The claim was that
the water pump could create over 30 PSI of pressure. *Since that is
double the normal operating pressure of most modern cars I find it
hard to believe. *If the system was at full 15 psi of pressure while
the car is idling and then your floored it and ran it up to near
redline * and created another 30psi of additional pump pressure, or
even 10 psi of additioingnal pressure downstream at the radiator cap, you
would immediately cause the system to have to vent to the overflow to
relieve this higher pressure. * I've never seen a car vent due to me
revving the engine up while I'm working on it. Thoughts?????


Hi.
There is a over flow bottle for coolant/anti-freeze. Ever
cleaned/flushed your rad. and maintain proper level of
coolant/anti-freeze in your rad.? If the car is old, messing with cap
can spring
a leak.- Hide quoted text -


- Show quoted text -


AMEN!


*A water pump cannot produce system pressure because it just moves
water from one side of the pump to the other. Expansion due to heat is
what builds pressure..- Hide quoted text -

- Show quoted text -


You might want to rethink that one. Water isn't going to
move through a system without pressure to push it. I wouldn't
expect the pressure to be very high, but there has to be pressure
due to the pump.

As for the question at hand, what is unstated is if there is
actually a problem, ie is the car overheating? If it is, then
finding out the cause of that instead of trying to raise the
boiling point of the coolant via pressure would seem to be
the better approach. For example, if he has a bad thermostat
or collapsing hose, he'd be just covering up the real problem.