Author Topic: Strange fuel gauge activity  (Read 1848 times)

Offline fiddler

  • Site Supporters
  • Registered Users
  • ******
  • Posts: 193
  • 74 Chevy C10 Stepside
Strange fuel gauge activity
« on: September 06, 2019, 07:01:40 PM »
I have a 1974 Chevy C10, (half ton stepside, 2 wheel drive).  I have a replacement fuel gauge from  .  The gauge reads relatively correctly, (slightly above full when full).  When I turn off the key, instead of remaining where it was it climbs as if the sensor line was open and there was voltage applied.  I have another fuel gauge from a 73 model that works and does not do the described behavior.  (I would use it but it does not have a window for the brake warning light).  When i turn the key back on the gauge goes to the correct position.  I cannot figure out what is driving the meter when the power is off.  Anybody seen such bizarre behavior on your fuel gauge??  Thanks for any response. 

Ricky

Online bd

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6438
Re: Strange fuel gauge activity
« Reply #1 on: September 06, 2019, 08:27:44 PM »
It is probably residual magnetism interacting between the gauge coils and gauge frame and should be of no significant concern.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline fiddler

  • Site Supporters
  • Registered Users
  • ******
  • Posts: 193
  • 74 Chevy C10 Stepside
Re: Strange fuel gauge activity
« Reply #2 on: September 11, 2019, 10:47:57 AM »
Thanks much!  I will go with that until I run out of gas and the gauge is telling my it still has half a tank.  That is what AAA is for...   
Ricky

Online bd

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 6438
Re: Strange fuel gauge activity
« Reply #3 on: September 11, 2019, 12:12:14 PM »
LOL.  If there is no power to the gauge (ignition off) and the dash grounds are healthy (no floating feedback loops), what else do you propose?  Personally, I would find it annoying and might try to degauss the gauge or substitute another, but it should not cause a problem, otherwise. 

Who knows what substitute materials, processes and quality controls have been employed in the manufacture of offshore-sourced components?  You could try contacting the vendor.  I suspect 50/50 odds that a replacement would function similarly.  In the meantime, be sure to carry your AAA card and a cell phone.   ;)
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline fiddler

  • Site Supporters
  • Registered Users
  • ******
  • Posts: 193
  • 74 Chevy C10 Stepside
Re: Strange fuel gauge activity
« Reply #4 on: October 03, 2019, 04:58:50 PM »
So it works great all the way to empty.  I filled at empty and it took 13 gallons plus.  That's close enough for me.  Usually I fill just below half....  Thanks for your inputs.

Ricky