lol.
I feel that way sometimes too.
good strategy is to wait and see what posts show up ..
consider those, add to them  ...etc.

temp gauge sender.. - as you say, is a  "temperature-dependent resistor."
Fuel gauge is similar., but with moving parts . ...
the sender supplies a variable connection to ground  that shows up on the
gauge.

with the temp sender, it just changes resistance inside the sender.
with fuel level float there is a sweeper arm on a float ..
and that acts on a potentiometer .

so 'normal' senders don't send out any voltage..
they operate in the ground side of the circuit, by supplying a variable
resistance to ground.

----- Original Message -----
From: "Mike "Rocket J Squirrel"" <camping.elliott@gmail.com>
To: "Scott Daniel - Turbovans" <scottdaniel@turbovans.com>
Cc: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, July 06, 2010 6:26 PM
Subject: Re: adding resister to center 1.9 coolant temp gauge?

> Wow -- I was way wrong! The sender is a temperature-dependent resistor?
>
> Shucks. I need to keep my mouth shut more often than I do.
>
> --
> Rocky J Squirrel
> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
> 74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
> Bend, OR
> KG6RCR
>
>
>
> Scott Daniel - Turbovans wrote:
>> lol,
>> re
>> "sender is a constant voltage source,
>> or a constant current source."
>>
>> the sender is neither.
>> but see Mark's post ..
>> if mark drillock says vanagons have square wheels....believe. it.
>> there isn't anything on this sort of issue he doesn't know everything
>> about.
>> Period.
>>
>>
>> ----- Original Message ----- From: "Mike "Rocket J Squirrel""
>> <camping.elliott@GMAIL.COM>
>> To: <vanagon@GERRY.VANAGON.COM>
>> Sent: Tuesday, July 06, 2010 5:43 PM
>> Subject: Re: adding resister to center 1.9 coolant temp gauge?
>>
>>
>>> This is a David Beierl question. Whether you add a resistor in series or
>>> in parallel depends on whether the sender is a constant voltage source,
>>> or a constant current source.
>>>
>>> Let's all step back, shall we? The David is about to speak...
>>> --
>>> Rocky J Squirrel
>>> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
>>> 74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.)
>>> Bend, OR
>>> KG6RCR
>>>
>>>
>>>
>>> Paul Guzyk wrote:
>>>> My 1.9 style dash coolant temp sender died.
>>>>
>>>> I replaced it with a new one.   Now the gauge reads high, about 65%-70%
>>>> when normal operating temperature instead of 50% (LED dead center) like
>>>> the old one.
>>>>
>>>> I'm thinking of adding a resister in series with the new temp sensor to
>>>> get the needle back in the middle.
>>>>
>>>> Anyone seen this before?
>>>> What value resister/pot did you add?
>>