Jeep XJ Fuel Tank Upgrade

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bassfishindoc

Rank IV
Launch Member

Traveler I

1,128
Middle TN
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6298

Hey all, having a bit of a fuel system issue, hoping someone here can help. I know this is an overland forum, and not Jeep XJ specific, but I’m hoping someone has upgraded to a larger Jeep XJ tank as well. I am also posting this at cherokeeforum.com to try and get all the info I can.

Here is my issue. I have a 1992 Jeep Cherokee (XJ) Laredo. It is currently undergoing multiple upgrades. I will be posting a thread about my build once it is more complete. I was removing the gas tank to repair some rusty floorboards when I noticed a small leak in the tank, as well as some rust around the tank. While this sucks, it is not too terrible as I am wanting to upgrade to a larger tank anyway.

GenRight Tank.jpeg

I have decided on the GenRight Fuel Tank (https://www.4wheelparts.com/Performance-Parts/GenRight-Fuel-Tank-GST-3003.aspx?t_c=74&t_s=433&t_pt=100904&t_pn=G/RGST-3003). It is 30.5 gallons, 10.5 gallons over stock! Additionally, it fits in the stock fuel tank location without modification, and has a built in skid plate. I know there are cheaper options suck as the Sunset Metal Fab AMC-2 which is 32 gallons and about $400 cheaper. However, it hangs too low and cannot accommodate a skid plate.
 

bassfishindoc

Rank IV
Launch Member

Traveler I

1,128
Middle TN
Member #

6298

Here is my issue. The new tank requires the newer (1997+) fuel-sending unit. As I understand it, the 1992 Jeep Cherokee sending unit and fuel gauge are 0 ohms empty, 90 ohms full. The new (1997+) fuel-sending units are 240 ohms empty, 33 ohms full. Please correct me if I am wrong with these numbers. I need to find a way to make the fuel tank compatible with my fuel gauge. I have searched and not come up with a great answer so far. Here are the options as I see them.

1. I have discovered that the new fuel-sending unit can be wired directly to the old wires and the pump will work. However, due to the difference in ohms, the stock fuel gauge will not work. Most guys who have done it this way have just used their odometer to estimate how much fuel is left. While doable, this is not really an option for me as I like to have an accurate fuel gauge.
 

bassfishindoc

Rank IV
Launch Member

Traveler I

1,128
Middle TN
Member #

6298

2. I can buy an aftermarket fuel gauge that is designed for the 240/33 ohms system. AutoMeter makes plenty of gauges that would work. I currently have the AutoMeter dual A-Pillar pod.

AutoMeter Pod.jpg

The top pod has this transmission temperature gauge mounted:

AutoMeter Trans Temp.jpg

AutoMeter also make a matching fuel gauge:

AutoMeter Fuel.jpg

Unfortunately, they only have it in the 0/90 and 73/10 ohm ranges. They do not make a Jeep 240/33 ohm gauge. There are 240/33 ohm gauges that come close, but none that match perfectly. By going this route I would have non-matching gauges, a stock gauge that I cannot remove as the instrument panel is one large piece so it would just sit there non-functional, plus I would use up my other A-Pillar pod which I was planning on using to mount a transfer case temp gauge. So, option 2 is better than option 1, but still not ideal.
 

bassfishindoc

Rank IV
Launch Member

Traveler I

1,128
Middle TN
Member #

6298

3. That leaves option 3, which is the point of this whole post. There has to be some way to adapt or convert the new tank and fuel-sending unit with the old fuel gauge. I have thought of a couple of possibilities and am looking to you guys to help me brainstorm and offer advice or suggestions.

Possibility 1: Here is the 1992 fuel sending unit:

1992 fuel pump.JPG

Here is the new fuel sending unit:

1997 fuel pump.jpg

For those of you with experience, can I straighten out and adapt the older style sending unit and make it fit into the same hole as the newer sending unit? This seems like it would be the simplest solution, but I do not know if the tank holes for the sending unit are the same size and style for the two different units. Any info or insights would be helpful.

Possibility 2: If the older style sending unit will not fit into the newer sending unit hole, is there a way to remove the 240/33 ohm sensor portion (not sure if that is what its called), and replace it with a 0/90 ohm sensor unit. I know AutoMeter and others make aftermarket units, and I could always steal the one off my current stock tank if its possible.

Possibility 3: Is there a device that can take the 240/33 ohm signal and convert it to a 0/90 ohm signal?

Possibility 4: Any other solution you all may have that I have not though of.

Thanks in advance for the help. I know my post is long, but I figure the more detail I can provide, the better responses I will get.
 

bassfishindoc

Rank IV
Launch Member

Traveler I

1,128
Middle TN
Member #

6298

I got some good advice on some of the other forums, wanted to close the loop here. The FuelLink sensor can convert any sender unit ohms to any fuel gauge ohms. It can also be customized if you have an oddball sending unit or fuel gauge. Simple solution for only $135. Also, it's not vehicle specific so if any of you are looking to upgrade your fuel tank size and need a different fuel sending unit, this may be a solution for you too.
FuelLink.jpg