Need fuel gauge help

[wjjeeper]

I've searched and read the other threads and can't seem to figure this out from them

65 c10, fuel in the tank, dummy light dash.

-I have a new fuel sending unit and new in cab tank. When the key is on the gas gauge is pegged to full. Removing the ground at the tank doesn't move the gauge. When the truck is off the gauge goes to empty.
-The wire from the fuse panel to the sending unit has power at the sending unit and I have a good ground at the sending unit.
If I put power to the back of the gauge itself it sweeps from empty to full.

What am I missing?

[wjjeeper]

pulled the sender and it doesn't seem to work

[luvbowties]

Originally Posted by wjjeeper

I've searched and read the other threads and can't seem to figure this out from them

65 c10, fuel in the tank, dummy light dash.

-I have a new fuel sending unit and new in cab tank. When the key is on the gas gauge is pegged to full. Removing the ground at the tank doesn't move the gauge. When the truck is off the gauge goes to empty.
-The wire from the fuse panel to the sending unit has power at the sending unit and I have a good ground at the sending unit.
If I put power to the back of the gauge itself it sweeps from empty to full.

What am I missing?

Sounds to me that gauge IS working, as it goes from E to F as keyed power is changed.
Please check that wire from gauge to sending unit is not partially rusted thru and grounding along its path between the two--path is likely underneath the sill moldings/floor mat, and wire is brown, iirc.. Happens v-e-r-r-r-y often.
Sam

[ACK]

Is it hooked to the factory gas gauge in the dash cluster or a separate aftermarket gauge? If aftermarket, it's likely a different OHM range, so it's showing full all the time.

[luvbowties]

Chev TRUCKS kept 0-30 ohms thru at least 1966--only cars went to 0-90 in 1966. HTH,
Sam

[ACK]

Originally Posted by luvbowties

Chev TRUCKS kept 0-30 ohms thru at least 1966--only cars went to 0-90 in 1966. HTH,
Sam

Thanks for the correction, above post has been edited.

[wjjeeper]

To update this thread. Tonight I got to changing the fuel sending unit in the tank and bingo. All works well. Hope this helps someone in the future with the same symptoms.