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Sleigher
06-06-2005, 04:56 PM
My fuel gauge is not reading correctly. I removed and cleaned the terminals on the tank and it didn't fix the problem,
I saw some little pots on the sender. Is it likely that they could be adjusted?
How do you know if you get it right?

Thanks for any and all help.

Peter

NoSlack
06-06-2005, 05:31 PM
I think Blackman went to a unit made buy Centroid for the tank sendor. There is a zero and full adjustment screw on the hockey puck sensor.
http://www.centroidproducts.com/dia9.jpg

The problem I found with these sensors is the condensation in my tank would drive the thing nuts.

The probe is a hollow aluminum tube with a sensing conductor running down the middle of it. The idea is the "hockey puck" would calculate the fuel level by sensing were the fuel bridged the gap between the tube and sensing rod.

The problem for me was moisture in the tank getting in the tube and bridging the gap above the fuel level and giving me a higher than actual reading. I would fill the tank and that would flood the sending unit with fuel and wash out the moisture. I was good to go after that until I let the boat sit for a few weeks with a 1/2 tank or less. Finally got feed up with it and went back to the old float and arm type sendor.

Mike

ps. test the gauge before you assume it's the sender. Touch both wires at the sender together and the gauge will go past the "F". Disconnect the wires and the gauge will read below "E".

To calibrate, remove the sender from the tank.
Make yourself a PVC tube that you can fill with fuel.
Hook the wires up to the sensor and set the zero with the sensor in the open air. Lower the sensor into your PVC test tube full of fuel and set the full adjustment. Repeat a few times until you happy with the repeatability of the gauge.

The link below should tell you everything you ever wanted to know about the sensor.
http://www.centroidproducts.com/2wire.htm

Sleigher
06-07-2005, 09:36 AM
Mike, as usual, you totally rock!

Thanks again,

Peter

DOGHOUSE26
06-07-2005, 05:40 PM
My fuel guage has been the abnormality in all the boats I have ever owned; it works like a champ every time! I will say however the second half of the tank goes by real fast, due to the "v" in the middle of the tank. At 1/2 tank gauge, I have approx 50-60 gallons left; 1/4 tank about 20 gallons.

NoSlack
06-07-2005, 06:58 PM
Centroid and custom build a sensor that compensates for the shape of the tank. Supply them with a drawing of the tank and they'll take if from there.

Mike