Date:         Fri, 6 Jun 2003 20:37:11 -0400
Reply-To:     David Brodbeck <gull@GULL.US>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Brodbeck <gull@GULL.US>
Subject:      Re: Cooling System performance at altitude
Comments: To: Pensioner <al_knoll@PACBELL.NET>
In-Reply-To:  <000601c32c8b$ad2ba1e0$4f0afea9@pacbell.net>
Content-Type: TEXT/PLAIN; charset=US-ASCII

On Fri, 6 Jun 2003, Pensioner wrote:

> If one has a 15psi cap will the coolant boil at a lower temperature at 7500
> feet than at sea level.  Same problem as a weight controlled pressure cooker
> and temperature degradation with altitude.  Both are "closed" systems.  Any
> ideas?

I believe it would.  Water's boiling temperature drops about 1 degree F
per 500 feet.  So, at 5000 feet you lose 10 degrees, and 7500 feet you
lose 15 degrees.  According to my coolant tester a 50/50 mix boils at 265
degrees with a 15 psi cap, presumably at sea level, so at 7500 feet I
assume it'd boil at 250F.  250F is probably hotter than you really want to
be running anyway, so this probably isn't an issue.

Anyone know offhand at what temperature the little red blinky-light comes
on?

David Brodbeck, N8SRE
'82 Diesel Westfalia
'94 Honda Civic Si