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Discussion Starter #1
I have a 1969 XR7 and the gas gauge only registers to the right side of the empty mark. When the key is off it goes all the way to the left below empty. Has anyone had any success removing the sending unit and rebuilding/cleaning the electronics themselves?
 

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Discussion Starter #3
It's a 2 year old tank with the original sending unit from what I was told. I need to get under her and see how many posts are on the sending unit. If it's a single post then they are easier to find than than the ones with the low fuel light sender..... Thanks
 

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Try removing the harness plug from the sender and grounding it. If the fuel gauge goes to full, you either have a tank grounding problem or a sender problem (more likely the latter).

I have carefully pried apart the tabs which hold the sender rheostat housing together, disassembled the housing, cleaned up the spring contact and winding (be careful of the winding, it's delicate), re-assembled and checked with an ohmmeter (check before taking apart too). The resistance should be about 10 Ohms at full and about 90 Ohms at empty.

If you have a low fuel sender (XR7 usually), the thermistor is almost always bad. Some people try replacing them, most are not successful. I sell an Electronic Low Fuel Indicator (ELFI) solution that allows you to use any sender with a good fuel gauge portion, low fuel or not. The ELFI develops the LF indication from the gauge signal.

Hope this helps you.

Regards,

Bob
 

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I've replaced my sending unit with one of Bob's ELFI units ... works great, reading is always accurate, and when the light comes on, I KNOW I'm low on fuel!! I highly recommend it.
 

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Discussion Starter #6
As the gauge does move some when the key is on I am assuming one of three things.... bad sending unit, stuck arm or hole in float. As this is a new car to me I am slowly learning it's idiosyncrasies! I assumed the tank was empty yet no fuel went in so it does have a full tank. I need to burn off some full so I can get the sender out. I also need to verify the number of pins on the sending unit. I had read the contacts can be cleaned but forget about the low fuel light (which is fine with me). The electrical unit you are speaking of goes where, behind the gauges?
 

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...The electrical unit you are speaking of goes where, behind the gauges?
The ELFI goes in place of the LF relay and yes, up until a certain date in '69 this is behind the cluster on the bottom of the cowl. After a date Ford began installing the LF relay and seat belt warning relay on a bracket near the radio in the lower dash.

The ELFI also requires changing your instrument voltage regulator out to a Solid State Instrument Voltage Regulator (SSIVR) which is also part of (and included with) the ELFI kit.
 

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Bob,
How much you getting for one of those. Not even close to instruments yet ... but will be eventually.
 

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Eric,

$113.50 shipped. The time to do this install is before you put the cluster in.

Did you receive the emails I sent?
 

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Not sure if 69 xr7 is the same, but on my 68 xr7, the stock LF relay was located behind the driver-side kick panel, not behind the dash where you'd expect it to be. And yes, Bob's ELFI is a great product. I highly recommend it.
 
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