Author Topic: Fuel sender ground missing...  (Read 1167 times)

Offline dave73chally

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Fuel sender ground missing...
« on: June 24, 2016 - 12:28:08 PM »
Looks like my fuel sender ground strap was cut off by the previous owner, half of it is hanging there. Regardless, my fuel gauge has been working fine...how is that? Is it being grounded by the clamp holding the fuel line to the chassis?

Found this when going to wire my new speedhut fuel gauge. Where should I attach to new gauge ground wire?
73 Challenger
512 / 4spd / Hotchkis & QA1 Suspension




Offline burdar

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Re: Fuel sender ground missing...
« Reply #1 on: June 24, 2016 - 12:39:20 PM »
The sending unit is grounding through the lock ring, fuel tank, tank straps.  The factory added the strap so the gauge would still work when the lock ring, fuel tank, tank straps rusted and stopped completing the ground.  I bought the short strap while restoring my 73.  I needed the long strap.  I haven't gotten around to installing it yet.  My gauge works too. 

The post that the sending unit wire attaches to is isolated from the sending unit body with a gasket.

Offline dave73chally

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Re: Fuel sender ground missing...
« Reply #2 on: June 24, 2016 - 10:52:02 PM »
I ordered the ground strap as well. Should I solder my gauge ground wire to that strap?
73 Challenger
512 / 4spd / Hotchkis & QA1 Suspension

Offline burdar

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Re: Fuel sender ground missing...
« Reply #3 on: June 25, 2016 - 04:03:25 PM »
The stock sending unit wire is the ground for the system. The sending unit varies the ground singal to change the gauge. What do the instructions for the new gauge say?

Offline Bullitt-

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Re: Fuel sender ground missing...
« Reply #4 on: June 25, 2016 - 04:07:32 PM »
I ordered the ground strap as well. Should I solder my gauge ground wire to that strap?

No that would cause the gauge to read full all the time. ...
connect gauge wire to the terminal on the sending unit..
strap is there to insure a good ground for the sending unit.
Wade  73 Rallye 340..'77 Millennium Falcon...13 R/T Classic   Huntsville, AL
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Offline lulurocks

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Re: Fuel sender ground missing...
« Reply #5 on: June 25, 2016 - 07:05:59 PM »
Dave,

I googled "speedhut fuel gauge wiring".  In 2 of there drawings is says

If your sender does not have a ground terminal  , don't connect it to anything .  Connect the white "signal in lead to the post on the stock sender ,  if your running a stock sender . 

My interpretation anyway ...

Ken