Date:         Thu, 28 Mar 1996 23:17:24 -0500
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         mjanello@umich.edu (Mark Janello)
Subject:      Re: Fuel gauge sender on 60's split

At 10:36 AM 3/28/96, Jonny Miner wrote:
>Having realized that the fuel gauge on my recently purchased '64 doesn't work,
>I headed to the tank to investigate. Lo and behold, was I surprised (not
>really) to find there was no wire heading from the sender to the gauge! There
>is just one wire coming out of the sender, which is grounded to the roof of
>the engine compartment. There is also a mystery wire coming from the cab which
>is not connected to anything. Gee, what a coincidence.
>
>My question is: There only appears to be one connection to the sender. Should
>I disconnect the ground and attach the gauge wire? Or is a ground neccesary as
>well? If so, where do I connect it? Both wires to the same connection?
>

There should be another connector on the sender.  The sender contains a variable
resistor, which changes as the float inside the gas tank moves up and down.
The gauge sends out a fixed voltage, which is sent first into a resistance
heater wrapped around a piece of bimetal in the gauge, then down to the
sender, through its resistor, then to ground.  The bimetal is attached to
the needle in your gauge,  so the amount of current absorbed by the sender
determines how hot the spring gets, and thus how far the needle moves.

Anyway, this is the long answer to your question, the short answer of which
is, don't hook the ground and the wire from the sender to the same place,
all you'll be doing is sending the maximum current through the gauge,
pinning the needle.  I think there is supposed to be a spade connector
on the sender.  I'll root around in the engine compartment of my '62
tomorrow and see if I can get some more info.

Mark
mjanello@umich.edu
'62 Kombi