[C320-list] Fuel sender puzzler...

[ptormey at 4square.net]

Just swapped out mine yesterday.
There is a great article on Catalina Direct 
https://www.catalinadirect.com/images/features/Engine%20Instrument%20technic
al%20information%20small.pdf?CFID=11371816&CFTOKEN=c62de31af7567fe8-7D6CD8B9
-93E2-5F5A-0C33CC2D2A9D8F81

Essentially, the gage is a voltmeter and the sending unit is a rheostat. As
the arm swing the resistance  runs between 35 ohms when full and 240 ohms
empty. You can read that with a multimeter from the pink wire on the gage to
ground. 

If always 'full' it means the sender in likely shorted to ground. Make sure
the connector on either end are not touching anything but their respective
terminals.

Mine was shorted and always ready "Full". I replaced it with Seachioce Fuel
Sender  model 15461

Good luck

Pat Tormey
Catalina 320 #1037
Blue Skies s/v
Newport, RI USA

-----Original Message-----
From: C320-list <c320-list-bounces at lists.catalina320.com> On Behalf Of David
Birken
Sent: Wednesday, August 10, 2022 9:17 PM
To: c320-list at lists.catalina320.com
Subject: [C320-list] Fuel sender puzzler...

The fuel tank on my C320 is not quite a cube but instead much deeper along
the forward section than aft. The fuel level sender is positioned in the
deeper part of the tank forward. I have just returned from a ~14 hour motor
and filled up just before leaving. The gauge still reads full after
returning and I ran pretty hard (3000 rpm) so I assume consumption was at
least 1/2 gal per hour or more.

The sender was just replaced 2 years ago. Any ideas on how to calibrate
this? Do I need to replace sender? How do I compensate for a trapazoid
shaped tank? Anyone with experience on this?? I appreciate all thoughts.