Author Topic: fuel gauge way past full  (Read 7350 times)

Offline ian75c10

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fuel gauge way past full
« on: March 02, 2015, 11:42:02 AM »
Hey guys so my fuel gauge has always read way past full when I fill the tank. It seemed as low as I could run the truck would be right when it hits E on the dot it would run out. Well the other day I ran out of gas at an 8th of a tank. Or even more that that according to the gauge. It way right between a quarter tank and empty when it ran out. Is there a quick fix in the dash that I can reset the gauge? I dont have any glass/plastic on my cluster over the gauges so I can actually touch the needle. I tried spinning it counter clockwise to read more accurate but it just goes back being too advanced. Is this something I need to get into the tank for? I have a carter 4070 fuel pump mounted under the tank on the frame rail. does this pump need more gas pressure from gravity because its more of a pusher than a puller? Thanks for the info in advance.

Offline zieg85

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Re: fuel gauge way past full
« Reply #1 on: March 02, 2015, 12:14:40 PM »
Full being at 3:00 is usually a bad ground but still having it go down might mean a resistor going bad on the back of the fuel gauge.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline ian75c10

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Re: fuel gauge way past full
« Reply #2 on: March 02, 2015, 12:17:34 PM »
Thanks, is the resistor something the autoparts might have and is it easily replaceable?

Offline zieg85

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Re: fuel gauge way past full
« Reply #3 on: March 02, 2015, 12:22:04 PM »
Thanks, is the resistor something the autoparts might have and is it easily replaceable?

Don't know, search the forum here I know it has been discussed in a thread not to long ago
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline rich weyand

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Re: fuel gauge way past full
« Reply #4 on: March 02, 2015, 01:19:36 PM »
Usually the gauge will read 1/4 at full and go down from there if the resistor is broken.
http://forum.73-87chevytrucks.com/smforum/index.php?topic=27370.msg227687#msg227687
Rich

"Working Girl": 1978 K-10 RCSB 350/TH350/NP203 +2/+3 Tuff Country lift

Offline ian75c10

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Re: fuel gauge way past full
« Reply #5 on: March 02, 2015, 05:18:07 PM »
I just took the whole cluster apart and cleaned the contact point for the fuel gauge, they did look old. I couldnt find the ground wire for not only the fuel gauge but the entire cluster. Put everything back together and still reading same fuel level.

Offline 76K20

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Re: fuel gauge way past full
« Reply #6 on: March 03, 2015, 02:05:33 PM »
I think they mean the ground at the fuel tank.

Offline enaberif

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Re: fuel gauge way past full
« Reply #7 on: March 03, 2015, 02:38:49 PM »
I think they mean the ground at the fuel tank.

Yes it gets corroded or falls apart. Unfortunately you gotta drop the tanks to get to it most times.

Offline 76K20

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Re: fuel gauge way past full
« Reply #8 on: March 03, 2015, 02:46:25 PM »
I think they mean the ground at the fuel tank.

Yes it gets corroded or falls apart. Unfortunately you gotta drop the tanks to get to it most times.

Or remove the bed

Offline FlatBlack77

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Re: fuel gauge way past full
« Reply #9 on: March 03, 2015, 10:33:20 PM »
my 79 does almost the exact same thing.

a full tank is like 2-2:30 on the gauge and empty is 1/8th.

and on my 77, full is full and empty is 1/8th. learned that the hard way.
"When you are a hammer, everything looks like a nail"
'77 C/10 - 350/350 mild street motor