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Fuel tank mystery: Here's what I found inside

pagrey

TJ Guru
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I ran the tank down to an uncomfortably low level on purpose beforehand. Here’s what the gauge read before I dropped the tank today. View attachment 302466

Most TJ gauges read like this. The tank isn't empty until the needle is to the left of the "E" Having plenty of fuel left in the tank with the needle in the position you posted is normal or at least normal for every one I've seen.

view.jpg
 
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Tim_with_the_tj

Tim_with_the_tj

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Vancouver, WA
Most TJ gauges read like this. The tank isn't empty until the needle is to the left of the "E" Having plenty of fuel left in the tank with the needle in the position you posted is normal or at least normal for every one I've seen.

View attachment 302848
Thanks. That’s good to know. I was still surprised to see over 4 gallons of fuel remaining when my needle was below E.
726259F1-0C27-4A83-A6F9-F9D9695A5837.jpeg
The sending unit was definitely bad. Now that the sending unit has been replaced I’ll be sure to keep in mind this reading is basically true empty. Here is what it looks like on full with the new sending unit.
435B7CAD-6788-4DC8-8F6A-03B2D34F05D2.jpeg
 
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Paparock1

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when my low fuel light comes on I look at the trip meter and figure I can go at least 65 more miles.

Put a 5 gallon jug of gas in the back and then drive until it runs out of gas. then you will know for sure
 
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Tim_with_the_tj

Tim_with_the_tj

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Yes I wouldn’t want to try that with 25 years of sludge at the bottom of the tank
Fwiw, with my new sending unit… when the fuel gauge reads 1/4 tank I know for a fact there is roughly ~6.5 gallons in the tank, because that’s what I put in there from it being bone dry after reinstalling it. Hope this helps anyone who was wondering, but doesn’t want to run their tank dry. This is assuming your gauge is reading correctly and your sending unit isn’t bad.

The TJ fuel gauge seems to read not-so-optimisticly considering it’s based on 19 gallons capacity and it reads 1/4 tank with ~6.5 gallons remaining.
 

SSTJ

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Fwiw, with my new sending unit… when the fuel gauge reads 1/4 tank I know for a fact there is roughly ~6.5 gallons in the tank, because that’s what I put in there from it being bone dry after reinstalling it. Hope this helps anyone who was wondering, but doesn’t want to run their tank dry. This is assuming your gauge is reading correctly and your sending unit isn’t bad.

The TJ fuel gauge seems to read not-so-optimisticly considering it’s based on 19 gallons capacity and it reads 1/4 tank with ~6.5 gallons remaining.

Also FWIW, and IIRC, the manual says that the light is supposed to come on when there are three gallons left in the tank.
 
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pagrey

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Yes I wouldn’t want to try that with 25 years of sludge at the bottom of the tank
The fuel pickup is at the bottom of the tank, the first gallon and the last are sucking the exact same 25 years of sludge. In fact the last drop of fuel out of the tank is much cleaner than the first few minutes after filling the tank with everything stirred up. There is no risk running a TJ out of fuel.
 

SSTJ

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The fuel pickup is at the bottom of the tank, the first gallon and the last are sucking the exact same 25 years of sludge. In fact the last drop of fuel out of the tank is much cleaner than the first few minutes after filling the tank with everything stirred up. There is no risk running a TJ out of fuel.

Interesting. That’s what I’ve always thought, from my boating days. But like most topics on this forum, I assumed that others knew something I didn’t.
 
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