fuel gauge reading wrong

[RivVrgn]

Hello fellas, have a problem with my gauge accuracy. A few years ago I replaced my sending unit because gauge was not reading correctly, gauge was showing less than what was in tank,(checked gauge by grounding it and it worked). Unit was original too and it showed when I removed it.

Anyway did not drive much last year so it wasn't an issue, but hopefully this year is different.

I bought a unit off e-bay that some others on hear had bought and said worked. when I installed it I also put an extra ground on it. put ten gallons in and reads just above E, if I disconnect the ground it changes nothing. If I disconnect the hot wire (yellow) gauge goes to full. I don't think it's the unit i'm thinking my hot wire is grounding out somewhere along the line.

I don't want to put more gas in it to see what it does if I just have to take it out to drop the tank again. when I had the tank out everything got cleaned and painted thats why I put an extra ground on it.

Is there an adjustment on those units? I just dropped mine in.

Any help is appreciated.

thanks Joey

[RivNut]

When you bought the unit off eBay; how was it described? If it said 63 - 65, the seller didn't know there is a difference. The '63 - 64 uses a 45 ohm sender, and the '65 uses a 90 ohm sender. Perhaps you've got the wrong one????? Hope not.

If it's possible, take the complete sending unit and the gauge to an electronics guy who can test them as a unit.

Ed

[coast]

Joey,

When I put mine in I got no reading on my gauge. I adjusted it by bending the arm, similar to adjusting the float in a toilet, lol. Once I did this it now works fine. I am a quarter of a tank off, still need to fine tune it.

Bob

[RivVrgn]

When you bought the unit off eBay; how was it described? If it said 63 - 65, the seller didn't know there is a difference. The '63 - 64 uses a 45 ohm sender, and the '65 uses a 90 ohm sender. Perhaps you've got the wrong one????? Hope not.

If it's possible, take the complete sending unit and the gauge to an electronics guy who can test them as a unit.

Ed

yeah, i thought that too Ed. It was bought as a 65 unit. like I said a few other people on here bought them and they worked fine. The thing that stumps me is the unplugging of the gauge and it goes to full. I am hoping for a fix that I don't have to drop the tank again, but it's not looking that way. thanks Ed

Edited May 9, 2014 by RivVrgn (see edit history)

[RivVrgn]

Joey,

When I put mine in I got no reading on my gauge. I adjusted it by bending the arm, similar to adjusting the float in a toilet, lol. Once I did this it now works fine. I am a quarter of a tank off, still need to fine tune it.

Bob

How was you adjusting done? Did you bend a little put it all back together, check it, take it apart again, bend a little more? wow. I guess I need to fill it uo to see how much I'm off then go from there. thanks Bob

[coast]

Did it two ways, first tried to match it up with the old one I took out. Second tried to estimate the amount of fuel in the tank then adjusted until the gauge matched what I felt was in the tank. I did miss by a quarter of a tank and did run out of gas because of it. I think if I pull it and adjust one more time I can get it very close. At least now I know that a quarter tank left on th gauge means empty. lol I parked it when I ran out of gas and have been out of town and have not messed with it. As I type this I am thinking that I might have a fuel pump issue. I dont know if it makes sense if the tank is empty, that I am showing a quarter of a tank. Have to give that some more thought. I do know though that when I put the sending unit in it showed empty until I bent the arm, then the gauge would move up. Hope this ramble helps

[Guest dwhiteside64]

Not to make an issue if it doesn't exist (you may have checked this already), but have you made sure the fuel gauge (i.e. dash unit) itself is functioning properly? If the internal coils/resistor are bad and worn out it could give you false reading too. Did you test the dash unit as described in the service manual? Just an idea.

[RivVrgn]

I have narrowed it down to somewhere on the tank. Either a ground or the sending unit itself. I have, I think, a pretty good ground. the one I purchased said it was for a 65, but if it wasn't how would it read if anything?

Also this one is stainless, would that affect the operation of the unit?

I recall someone saying on here about someone who rebuilds original units but could not find anyone in the Riview. Does anyone know of someone in case I go that route?

thanks, Joey

[Desmc14]

I have the same problem - really annoying.... It is off by quarter tank each way... when full shows 3/4...... I bought it from Rancho Riviera.... I am sure he sent me the wrong one... it looked different - I put in anyway and sent my core back to him - big mistake... hasn't read properly for three years.... arrghhh!

Edited May 23, 2014 by whalerman03 (see edit history)

[RivVrgn]

Just thought I'd close the book on my problem. after fiddling with things, got a good ground and ended up bending the float on the new unit to match the old one (Bob). Still off a little bit, but in a good way, it reads lower than it is. So, at empty I have a few gallons left. thanks for all the input.

[coast]

Glad you got it dialed in. I still need to dial mine in a little closer, have other more pressing items I need to address first. lol.

[60FlatTop]

Top the tank off every Sunday evening or after 200 miles. It is a nice way the wrap up a weekend, especially if you have more cars than a sane person.

In 1978, when I bought the car, gas was about $0.75 a gallon. Back then I didn't even keep my driver full. Gas is 4 bucks a gallon now and the whole fleet is topped off. I drive on biased tires and think the economy is better for me than 35 years ago. Must be me.

Bernie