<VV> Head Temp Sensor

[MarK Durham]

You cannot switch from one type to another sensor with the same gauge or
wiring. Neither systems parts are compatible with the other. They operate
on totally different principles.

The Thermocouple system is independent and does not rely on the car's
electrical system other than for a light for the gauge, if installed.
Dis-similar metals in the copper ring generate and send varying voltages to
the gauge as the temperature changes. The wiring harness is a part of the
thermocouple and must not be tampered with.

The thermister system is no different than other gauges.Power goes through
the gauge, down the wire and through the thermister to ground. The amount
of current that flows (that moves the gauge needle) depends on the
temperature of the thermister.

Just get a VDO system, make sure you order the correct length thermocouple
wiring for your application, and install it all. Find a bolt (preferrably
stainless steel to avoid corrosion issues) with the correct thread for the
thermister hole, use a stainless steel wide washer that will cover the
thermocouple fully on top of the copper thermocouple, and tighten it up on
the head surface. The bolt will transfer heat from the same threads the
thermister would use, as well as contact with the head surface, and you
should get fairly reliable accuracy out of the kit.


Mark Durham
Hauser, Idaho
62 Monza coupe Red/Red 4 speed

On Fri, Jul 10, 2015 at 9:31 AM, frankcb--- via VirtualVairs <
virtualvairs at corvair.org> wrote:

>
> JR and Barry,
> `    I suspect that the thermistor type setup (like the stock Corvair
> 140/180) depends on the resistance of the thermistor probe changing with
> temperature, so the gauge is setup to respond to that.  But the spark-plug
> type depends on a thermoelectrical signal sent from the part under the plug
> back to the gauge.  So I question if you can switch senders from one type
> to another without switching gauges to the type that the specific sender
> requires.
>     Maybe someone who really knows this stuff will jump in here to respond.
> Frank Burkhard
> Boonton, NJ
>
>
> -----Original Message-----
> From: J. R. Read via VirtualVairs <virtualvairs at corvair.org>
> To: Gary Berry <duallycc at gmail.com>; Virtual Vairs <
> VirtualVairs at corvair.org>
> Sent: Thu, Jul 9, 2015 8:07 pm
> Subject: Re: <VV> Head Temp Sensor
>
>
> Uhh, a themirster - in the original spot?
> Later, JR
>
> ----- Original Message
> -----
> From: "Gary Berry via VirtualVairs" <virtualvairs at corvair.org>
> To:
> "Virtual Vairs" <VirtualVairs at corvair.org>
> Sent: Thursday, July 09, 2015 5:09
> PM
> Subject: <VV> Head Temp Sensor
>
>
> > Hey All;
> >
> >   I have an old head
> temperature gauge in my buggy that has the actual
> > sensor under one of the
> sparkplugs. It doesn't work anymore. I would like
> > to replace this with a new
> modern one. Any recommendations? Anything
> > rather
> > than under the
> sparkplug? Thanks.
> >
> > --
> > GaryB in Wa.
> > 1969 ManxVair
> > 1971 Corvair
> Turista
> > _______________________________________________
> > This message was
> sent by the VirtualVairs mailing list, all copyrights are
> > the property
> > of
> the writer, please attribute properly. For help,
> >
> mailto:vv-help at corvair.org
> > This list sponsored by the Corvair Society of
> America,
> > http://www.corvair.org/
> > Post messages to:
> VirtualVairs at corvair.org
> > Change your options:
> >
> http://www.vv.corvair.org/mailman/options/virtualvairs
> >
> _______________________________________________
>
>
> ---
> This email has been
> checked for viruses by Avast antivirus software.
> http://www.avast.com
>
>
> _______________________________________________
> This message was sent by the
> VirtualVairs mailing list, all copyrights are the property
> of the writer,
> please attribute properly. For help, mailto:vv-help at corvair.org
> This list
> sponsored by the Corvair Society of America, http://www.corvair.org/
> Post
> messages to: VirtualVairs at corvair.org
> Change your options:
> http://www.vv.corvair.org/mailman/options/virtualvairs
>
> _______________________________________________
>
>
>  _______________________________________________
> This message was sent by the VirtualVairs mailing list, all copyrights are
> the property
> of the writer, please attribute properly. For help, mailto:
> vv-help at corvair.org
> This list sponsored by the Corvair Society of America,
> http://www.corvair.org/
> Post messages to: VirtualVairs at corvair.org
> Change your options:
> http://www.vv.corvair.org/mailman/options/virtualvairs
>  _______________________________________________
>