Inaccurate fuel level reading

Discussion in 'Tech Discussion' started by Xman, May 6, 2018.

  1. Xman

    Xman Member

    Posts:
    32
    Likes Received:
    0
    Joined:
    Sep 27, 2015
    Location:
    Coral Springs, FL
    First Name:
    Rick
    Truck Year:
    1987
    Truck Model:
    R10
    Engine Size:
    350
    My fuel gauge reads a little over 1/4 of a tank of fuel when full. The truck has dual tanks and the gauge reads the same way on either tank. Because of that fact, I'm thinking the gauge is the problem. However, I wanted to check with folks in the know if anyone has experienced this as it could possibly be a ground issue at the gauge or sending units. Any ideas on how to get a full reading on the gauge?

    Thanks
     
  2. theblindchicken

    theblindchicken Full Access Member

    Posts:
    1,381
    Likes Received:
    170
    Joined:
    Oct 24, 2013
    Location:
    SoCal
    First Name:
    Christian
    Truck Year:
    1974
    Truck Model:
    K10 5" lift + 2" BL
    Engine Size:
    350-4, 0.030" over
    Does it only read between Empty and 1/4 full? If so, i'd take a look at the gauge. If I remember correctly, it will max out if it has an open circuit.
     
  3. mavtricks71

    mavtricks71 Full Access Member

    Posts:
    124
    Likes Received:
    22
    Joined:
    Jun 29, 2016
    Location:
    az
    First Name:
    mike
    Truck Year:
    1986
    Truck Model:
    k10
    Engine Size:
    350
    I put 2 Spectra Fuel sending units in my 86 K10 truck they are very good....might be sending unit getting old
     
  4. 1987 GMC Jimmy

    1987 GMC Jimmy Full Access Member

    Age:
    21
    Posts:
    3,795
    Likes Received:
    811
    Joined:
    Jan 23, 2016
    Location:
    New Orleans, LA
    First Name:
    Jesse
    Truck Year:
    1987
    Truck Model:
    V1500 Jimmy
    Engine Size:
    350
    I second the gauge. But yeah, Spectra seems to make a solid product. I've got 16,000 miles on sender that I installed, and it's done just fine.
     
  5. Xman

    Xman Member

    Posts:
    32
    Likes Received:
    0
    Joined:
    Sep 27, 2015
    Location:
    Coral Springs, FL
    First Name:
    Rick
    Truck Year:
    1987
    Truck Model:
    R10
    Engine Size:
    350
    Yes, gauge only reads between empty and 1/4. Both sides. Going to get a new gauge. Btw... could it be the printed circuit behind the gauges somehow? I'll surely find out when the gauge is removed I suppose.
     
  6. Blue Ox

    Blue Ox Full Access Member

    Posts:
    332
    Likes Received:
    266
    Joined:
    Mar 27, 2018
    Location:
    LI-NY
    First Name:
    Derek
    Truck Year:
    1985
    Truck Model:
    K20HD
    Engine Size:
    6.2L
    It could be. We had issues with ours because of oxide buildup where the contact clip met the circuit board. Did you try disconnecting and grounding one of the sender leads to see if the gauge will go to max and min? Could save you pulling the cluster apart.
     
    Xman likes this.
  7. Xman

    Xman Member

    Posts:
    32
    Likes Received:
    0
    Joined:
    Sep 27, 2015
    Location:
    Coral Springs, FL
    First Name:
    Rick
    Truck Year:
    1987
    Truck Model:
    R10
    Engine Size:
    350
    Blue Ox, I will try that. Thanks. I assume that is at the gauge itself?
     
  8. Blue Ox

    Blue Ox Full Access Member

    Posts:
    332
    Likes Received:
    266
    Joined:
    Mar 27, 2018
    Location:
    LI-NY
    First Name:
    Derek
    Truck Year:
    1985
    Truck Model:
    K20HD
    Engine Size:
    6.2L
    I was thinking at a tank sender or somewhere else you can access the lead like the connector on the selector valve.
     
  9. Norwester

    Norwester Full Access Member

    Posts:
    112
    Likes Received:
    4
    Joined:
    Jul 3, 2015
    Location:
    Battle Ground, WA
    First Name:
    David
    Truck Year:
    1986
    Truck Model:
    C-10
    Engine Size:
    350
    I have the large fuel gauge out of my '86 that you can have for the cost of postage. Worked fine when I pulled it. I did so to install the tach/fuel gauge that I got my GM Sports.
     
    Xman likes this.
  10. Splandman

    Splandman Full Access Member

    Age:
    47
    Posts:
    252
    Likes Received:
    34
    Joined:
    Jan 1, 2014
    Location:
    Crescent, OK
    First Name:
    Scott
    Truck Year:
    1982
    Truck Model:
    K10
    Engine Size:
    383
    I was wondering about these sending units. I am about to convert my truck to in tank pumps and was looking at the spectra sending units for the 87 tanks. They aren't too expensive but I was wanting to hear what someone who bought them thought. Guess I will give them a shot.
     
  11. Xman

    Xman Member

    Posts:
    32
    Likes Received:
    0
    Joined:
    Sep 27, 2015
    Location:
    Coral Springs, FL
    First Name:
    Rick
    Truck Year:
    1987
    Truck Model:
    R10
    Engine Size:
    350
    Norwester, Thanks but I have already ordered a new gauge. Thanks again!
     

Share This Page