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Old Jan 12, 2013 | 06:58 PM
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fuel sending unit

i have a 79 f150 and the fuel gauge reads full all the time,so i dropped the tank and bought a 19gallon sending unit,but when i dropped the tank its the 38gallon.so i put the extension kit on it,now it reads empty?is there a certain way the sending unit goes in tank?
 
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Old Jan 12, 2013 | 07:02 PM
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i put 17gallons in it,i guess i have to go over 19gallons to see if it goes up?
 
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Old Jan 12, 2013 | 07:17 PM
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Did you bend the arm during install? Or compromised the sending unit wire in some way?

Josh
 
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Old Jan 13, 2013 | 09:40 AM
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no,but dont know if it maters which way the sending unit goes in tank,could i have it up side-down?
 
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Old Jan 13, 2013 | 10:10 AM
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I thought it only goes in one way... The arm should point towards the back of the truck

Josh
 
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Old Jan 13, 2013 | 10:22 AM
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Originally Posted by btracy
I have a 79 F150 and the fuel gauge reads full all the time. So, I dropped the tank and bought a 19 gallon sending unit, but when I dropped the tank, it's the 38 gallon.

So, I put the extension kit on it. Now it reads empty?
No such thing as a 38 gallon tank for any 1973/79 F100/350. 1979 F150 2WD would have either a 19 gallon aft axle or 20.2 gallon mid-ship tank.

The sending unit can only "go in" one way. Impossible to install 'upside down' as it's composed of a crooked arm the float attaches to and the fuel pickup tube.
 
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Old Jan 13, 2013 | 11:18 AM
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ok,let me ask this way,then sending unit in tank will the gas line tube be on bottom and electrical connect on top?
 
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Old Jan 13, 2013 | 11:26 AM
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also i seen a blackburn splice reducer,so i can extend the crooked float arm on my sending unit for the 38gallon tank.boy ill never be able to afford to fill this tank.

dear,numberdummy if you look at lmc website you'll find a 38gallon REPLACEMENT tank.this is why i'm having the problem,but thank u so much you have been helpful on all my posts.
 
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Old Jan 13, 2013 | 12:48 PM
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Electrical connector on top with siphon tube and float pointing rear wards.

Normally with the 38 gallon tank it should read full until it reaches 19 gallons and then the gauge will behave like normal.

If the connector is attached and yet reading empty uou either have a defective sending unit or the wire somehow broke.

Grounding the sending unit wire to the frame should make the gauge peg full if the wire is good and the gauge is operating correctly..

Josh
 
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Old Jan 13, 2013 | 01:28 PM
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im going to put more gas and see if it starts reading.
 
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Old Jan 13, 2013 | 01:56 PM
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Originally Posted by btracy
im going to put more gas and see if it starts reading.
Just take the sending unit wire and ground to the frame. If the gauge legs full then you know the gauge works and wiring is fine at the connector.

Then you can move on to troubleshooting the sending unit.

Josh
 
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Old Jan 14, 2013 | 05:23 AM
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Originally Posted by btracy
NumberDummy, if you look at lmc website, you'll find a 38 gallon REPLACEMENT tank. This is why I'm having the problem.
Why would I (or anyone else) think to look at LMC's website to discover it's their aftermarket 38 gallon fuel tank your truck has?

When you ask a question, it's your job to list all the pertinent info.

People aren't mind readers, so if you don't list what is pertinent, how would anyone know?
 
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Old Jan 14, 2013 | 06:25 AM
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i'm getting to think you might be touched with a little alzheimer's,if you LOOK at the first post i put up,i said i pulled out a 38 GALLON. HELLO.also you counter dictate your self on another post i put up,so i don't want to be mean,but to save a argument don't reply to my post.THANK YOU.
 
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Old Jan 14, 2013 | 06:32 AM
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Originally Posted by btracy
i'm getting to think you might be touched with a little alzheimer's,if you LOOK at the first post i put up,i said i pulled out a 38 GALLON. HELLO.also you counter dictate your self on another post i put up,so i don't want to be mean,but to save a argument don't reply to my post.THANK YOU.
Originally Posted by btracy
when i dropped the tank its the 38gallon.
You don't seem to "get it."

You said your truck had a 38 gallon tank, but you failed to mention it's an aftermarket tank.

Since there were no 38 gallon tanks available from Ford, I assumed you were mistaken as to its capacity.

I'm 68 years old, with an IQ of 163, and a 90/95% memory retention, so I don't forget much.

And if I typed a question, I certainly would not forget to list all the pertinent info!
 
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Old Jan 14, 2013 | 06:53 AM
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well,if ford didn't make then,its aftermarket,i didn't miss typo.i can get that your VERY knowledgeable about ford trucks,BUT most of us are back yard mech,that's why we need this web site.so yes we are going to miss some info,but since your so knowledgeable,i would think you can understand what the topic is about and not over analyze our computer skills.again sorry about being backlashing.
 
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