fuel sending unit

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69DARTS

69DARTS

69 Darts Rule
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in my 72 duster my fuel sending unit is 1/2 off
when the gauge is on E it has a 1/2 tank
gauge is working i think its the sending unit
when the gauge says full its full .
this is a new unit
any help thank u tel me where to start
 
The new ones aren't calibrated correctly. In fact, if you compare it side by side with the original A-body sender, it pivots at a different point, has a different length and shape arm, and a different scale. So it's no surprise it doesn't read the same. I gave up on the new ones and found an old one where someone had upgraded to a larger fuel line (3/8 instead of 5/16) and was willing to let a good sender go. I'd recommend you try to do the same.
 
All the new china senders read that way and even the ones from mexico that are supposed to be good read bad.I just installed a new one and it reads sorta like yours.10 gal reads empty,15 gal reads 1/4 and goes to full when full.
 
I bought a new one last year. I bent the float arm to same as stock original. Mine works fine
 
I know I cant educate the world. I really should just give up. Look at this...
[ame="http://www.ebay.com/itm/Eico-1171-Resistance-decade-box-/281358605562?pt=LH_DefaultDomain_0&hash=item4182479cfa"]Eico 1171 Resistance Decade Box | eBay[/ame]
That was easier than taking a pic of my workbench this morn. Anyway...
If our gauges were designed with time piece like movement they would respond to every increment in resistance change. Then service techs would have used equipment like this to test the gauges. Fact is the gauges were not so sensitive and/or accurate.
The service techs used a 3 point tester. If the gauge responded to empty, half tank, and full it is/was considered good.
Why 20 ohm gauges are much more sensitive and accurate than the 13 ohm gauges and why 20 ohm gauges don't live as long is just too complicated to try and explain.
I'll add a pic of a 20 ohm gauge for example... You would be hard pressed to find a 13 ohm gauge that looks like this inside. They don't run as hot.
The member name Pawned and others have pics of 13 ohm gauges for comparison. they can see the difference in movement design. 20 ohm gauge shown has a pin in a slot driving a heavier needle. 13 ohm gauge needle weighs nothing and attached with a ring so its more a chain link attachment.
Even though the 13 ohm gauge lives longer, it does loose sensitivity. Test it with the factory standard 3 point tester and it will look good but by design... The sender resistance signal might go from 10 or 12 all the way to 30 before the gauge needle moves from full to half. The when the resistance signal changes from around 30 to around 45 the needle drops all the way to empty. I'm going to call the movement in the 13 ohm gauge a seesaw effect ( for lack of a better description ).
 

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66Dvert said:
umm care to give a reason? instead of just saying "Beware" would be nice. like he rips people off or doesn't do the work right ect... or you don't like his page or something. cause just saying so isn't helping.

how bout these guys
http://www.bobsspeedometer.com/1/120/services.asp
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I sent him my perfect working ss sending unit to get a return line to get a ss return put in it cost me 9 dollars to send it to him . he said he would call me before any work was done with a estimate well he calls me and says its done and it cost 160.00 and he said he replaced the part where the push on wire goes . so he sends it back to me and charges me 40 bucks and then he fill out the paperwork wrong so there is a 40.00 $ border fee . so when I get the unit it has the wrong wire hookup so he tells me to just cut my new wire end and put a different end on it . so before cutting anything I thought I would test it first and it dosent even work and he wont do a thing for me or stand behind his work. I have nothing more to say.
 
jimjimjimmy said:
I sent him my perfect working ss sending unit to get a return line to get a ss return put in it cost me 9 dollars to send it to him . he said he would call me before any work was done with a estimate well he calls me and says its done and it cost 160.00 and he said he replaced the part where the push on wire goes . so he sends it back to me and charges me 40 bucks and then he fill out the paperwork wrong so there is a 40.00 $ border fee . so when I get the unit it has the wrong wire hookup so he tells me to just cut my new wire end and put a different end on it . so before cutting anything I thought I would test it first and it dosent even work and he wont do a thing for me or stand behind his work. I have nothing more to say.
Click to expand...



Whoeee! that is a darn good reason. thanks for the clarification.

I'll check out the other couple of guys I found on google to see if their work holds up when I get that far on mine
 
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