Fuel gauge off about 1/4 high ?

[ZEKE68]

My fuel gauge reads about 1/4 tank high. When full its about 1/4 past full. and when empty it never goes below 1/8 tank. 1/2 tank reading is over 3/4 in the tank. I grounded the lead but the gauge won't go any lower than 1/8. Could the ohms be mismatched? or just something to live with? Bad gauge?

[TBONE1964]

Originally Posted by ZEKE68

My fuel gauge reads about 1/4 tank high. When full its about 1/4 past full. and when empty it never goes below 1/8 tank. 1/2 tank reading is over 3/4 in the tank. I grounded the lead but the gauge won't go any lower than 1/8. Could the ohms be mismatched? or just something to live with? Bad gauge?

I would pull the sender and bench test it with a ohm meter. While it is out, check the float to make sure it is good and not taking in fuel.

Also you can hook up your sender wire and put a ground on it and do the test right inside the truck and watch what happens. It is possible your float arm is out of adjustment causing the 1/8 tank reading. If you pull the sender and the gauge now goes to empty, then the float arm needs adjusted.

Not uncommon to get more than full with some aftermarket senders. You should get full tank at 90 ohms. If you get 115 ohms at full, then the needle on the gauge will travel further.

I would do a complete ohm sweep on the sender and make sure it is not wigging out and giving false readings.

Not likely the gauge is bad if it moves through the complete range.

Before any of that have you had the needle off the gauge to paint it, or do you know of the history of the gauge? Sometimes needles get pulled and not placed back correctly. I use a factory sender to set my needles after restoration.

Hope any of this helps,
Tom

[ZEKE68]

That was with the sender out of the tank. sender bottomed out, the gauge read 1/8 tank. Damn I wish I had taken an ohm reading when I had it out. I was moving the sender through its range.

[ncpetersc]

If you ground the lead and it still shows 1/8, doesn't sound like sending unit, maybe look the other direction. As in, the lead/wire, or the gauge itself. Also, how are you grounding it? If you are grounding it to the tank, check to make sure that the tank itself is grounded and/or try grounding the wire to something else like the cab.