Date: Sun, 14 Mar 2010 21:03:24 -0500
Reply-To: Tom Hargrave <thargrav@HIWAAY.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tom Hargrave <thargrav@HIWAAY.NET>
Subject: Re: weekend work
In-Reply-To: <5d9ac4c91003141719t525c7308yebcf2cd92830b8b3@mail.gmail.com>
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I've always argued against using a under-rated thermostat unless recommended
by the manufacturer. Most of the time if you are running an underrated
thermostat you are really masking a problem somewhere and that problem is
just waiting to wake up and bite you.
Tom
www.kegkits.com
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM] On Behalf Of
Ry
Sent: Sunday, March 14, 2010 7:19 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: weekend work
Interesting and sounds like a good argument against using a lower rated
thermostat. That being said, I would be curious about the physical process
the thermostat goes through as it's rated temperature is reached. I read
that thermostats in automobiles work by a calibrated wax filled chamber,
when cool the wax is solid and when it heats up it becomes liquid.
So I thought maybe this would happen all at once. So i grabbed my 87C rated
thermostat and put it in a pot of water. The wax is turning to liquid,
expanding due to heat and slowly opening. This would lead me to believe it
does more regulation than just closing off flow to a cold engine until the
engine warms up then opening and staying open. The thermostat is going to
vary in "openness" as temperature fluctuates. Thus I would say that having a
80C rated thermostat could effectively keep your engine cooler. I'm NOT
saying that's good for the engine, just saying, that's my theory based on my
observation.
peace,
-Ry
http://www.google.com/profiles/rylincoln
On Sun, Mar 14, 2010 at 6:19 PM, <mcneely4@cox.net> wrote:
> Last summer, when I was having oil pressure monitoring problems, and
> thought the oil pressure on my van was low, I was having cooling
> problems as well, and was driving at temperatures above 100 F. I
> suspected that the van running hot caused the oil pressure to be lower
> than it should be. One fix I thought of to get the van to run cooler was
to put in an 80 C thermostat.
>
> I didn't do that. Think about it. The point of the thermostat is to
> allow the coolant to heat to operating temperature. Once it reaches
> that temperature, the thermostat is going to stay open, and have no
> further effect on coolant temperature. The engine will run at a
> temperature determined by engine operation (heat generation), coolant
> circulation (heat distribution), and the radiator (heat removal).
>
> The waterboxer is designed to run at 87 C or hotter, not cooler. But,
> if you have an 80 C thermostat, it will open at 80 C. If the engine
> is overheating, it will still overheat, and to the same degree. If
> there are cooling problems, those need fixed. I went so far as to get
> a new radiator, and to flush the coolant multiple times. Got things
straightened out.
> However, I did put in a fan switch that turns on the fan at a
> slightly lower temperature (I think it is 2 degrees C cooler). It
> does not make the engine run too cool.
>
> I'm not sure why the 80 C thermostats are available (but there is also
> a 78 C thermostat, I think).
>
> DMc
>
> ---- Ry <rylincoln@GMAIL.COM> wrote:
> > Well I got my engine almost back together. Still waiting on the new
> > oil cooler.
> > pic(s)
> >
> http://picasaweb.google.com/lh/photo/h0p5TUIV6Ka4grfT1NhzZQ?feat=direc
> tlink
> >
> > the plan is to lift it up and bolt in tomorrow if all goes well I'll
> > be working out the kinds by tomorrow evening.
> >
> > anyone in a hot climate(i'm in Texas) using an 80C thermostat?
> >
> > peace,
> > -Ry
>
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