Date: Sun, 13 Feb 2000 22:10:50 -0500
Reply-To: John Koloski <koloski@TOAD.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Koloski <koloski@TOAD.NET>
Subject: Re: coolant pressure gague
Content-Type: text/plain; charset=ISO-8859-1
Dana Morphew's idea is an excellent one! The rabbit - golf's expansion
tank is MUCH closer to the dashboard than the vanagon's expansion tank.
For the vanagon, you would want an electronic pressure sender on the
vanagon's expansion tank, wired to a gauge on the dash, twenty feet of wire
away.
The system is defined by the walls containing it. When you blow a
radiator hose, the system is no longer contained by the walls around it
(actually the system is still defined by the walls around it, but the walls
around are being redefined relatively rapidly). Liquid and gas are at
equilibrium in the sealed system, that is to say that, even though the gas
is extremely compressable, and the liquid is relatively incompressable,
they exert equal and opposite forces upon one another in the limit defined
by the walls of the closed system. PV=nRT it's not just a good idea, IT'S
THE LAW. http://www.toad.net/~koloski
> From: Caston/Payne <happycampers@PICUSNET.COM>
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: coolant pressure gague
> Date: Sunday, February 13, 2000 11:32 AM
>
> At 11:37 AM -0800 2/12/2000, Dana Morphew wrote:
> >I bought a cheap, unlit, 0-30psi, 1 1/2" gauge from Princess Auto for
> >$3. This was for my Rabbit, but it would work for a Vanagon.
> >
> >I drilled a hole into my expansion tank above the max. water level and
> >close enough to the tank cap to be able to fit a washer and a nut onto
> >the silicon caulked threads of a brass, barbed, fitting with a male
> >threaded end. I ran a length of hose through the firewall and attached
> >the ends to the barbed fitting and to the gauge, using clamps. No
> >coolant and only air in the line (the gauge is 'air only').
> >
> >It shows 7psi when I climb the 1/2 mile long, 9% grade hills around here
> >and 5psi on the flats at 60mph. The rad. fan comes on at 10psi and
> >turns off at 8psi, so we are not dealing with large pressures.
>
> >-Dana-
>
> This is certainly easy enough sounding. I wonder, however, if the
pressures
> you are observing are accurate or not. I say this because air is more
> easily compressed than liquids and there are 2 different states of matter
> here. Any chemists or physicists care to comment?
> Later,
>
> Dave C.
> Williamsburg, VA
> zzzzzzzzzz__
> |E[__] [__]|[_]\\
> | _DC&SP | _ ||
> * * * =-( )---------( )--=
> '85 GL Westy (His)
> '91 Cabriolet (Hers)
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