Thread: 68 sending unit
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Old 07-04-2017, 07:37 PM   #2
dennislbrooks
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Join Date: Feb 2004
Location: Williamsburg, Ohio
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Re: 68 sending unit

Happy 4th. Usually if the needle showed past full the connection from the tank --tan wire- has no ground- infinite resistance --completely open circuit.

If nothing has changed at the gauge and the fuse on the block for fuel is ok, with the key in on position, touching the tan wire to a solid ground should show on the gauge ---empty.

If this is so --- make sure the new sending unit housing on one of the top 5 or 6 screws has a permanent jumper wire to a solid ground.

The tan wire connects to the nutted stud on top of the gas tank sending unit. The sending unit controls the ground resistance --depending on amount of gas in tank--- back to the gauge.

You can test the new sending unit out of the tank with the jumper wire to ground , the tan wire on the stud, and moving the float slowly up and down before you put in the tank and before putiing gas in the tank. If you get needle movement in the correct directions -- probably good to go.

Usually from my experience, if the gauge reads past full ---gauge is probably ok.
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Last edited by dennislbrooks; 07-04-2017 at 07:42 PM. Reason: words
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