Fuel level sending unit

[Gollywomper]

My fuel gauge has always read a bit off. It is very consistent, just not accurate to the amount of fuel In The tank. It will drop to 3/4 tank after using 1.5-2 gallons of fuel. Then to half after about the same. From 1/2 down to the light seems to be ok but when the light comes on it still has over 5 gallons in the tank. So being it is a 4cyl it goes from full to low level light on with only 10 gallons of use.
Today while looking for an assembly to replace I found a mopar sending unit. It comes up for my 4cyl on rock auto but says for a 19 gallon tank. Any idea if they 15 & 19 gallon tanks use the same sending unit?


https://www.rockauto.com/en/catalog...+l4,1316013,fuel+&+air,fuel+sending+unit,4436

 

[pagrey]

It does sound like you have the 15 gallon vent with a 19 gallon sending unit if there is such a thing. I'd just mod the tank so it's 19 and see where you are. Four gallons is normal for the light to go on, five is a little off but not by much.

 

[Gollywomper]

It does sound like you have the 15 gallon vent with a 19 gallon sending unit if there is such a thing. I'd just mod the tank so it's 19 and see where you are. Four gallons is normal for the light to go on, five is a little off but not by much.

I though about that as well but I would think it would read not full. Isn’t there a way to mod the 15 gallon tank?

 

[Jerry Bransford]

My fuel gauge has always read a bit off. It is very consistent, just not accurate to the amount of fuel In The tank. It will drop to 3/4 tank after using 1.5-2 gallons of fuel. Then to half after about the same. From 1/2 down to the light seems to be ok but when the light comes on it still has over 5 gallons in the tank. So being it is a 4cyl it goes from full to low level light on with only 10 gallons of use.
Today while looking for an assembly to replace I found a mopar sending unit. It comes up for my 4cyl on rock auto but says for a 19 gallon tank. Any idea if they 15 & 19 gallon tanks use the same sending unit?


https://www.rockauto.com/en/catalog...+l4,1316013,fuel+&+air,fuel+sending+unit,4436

Sounds perfectly normal and consistent with how my gauge indicated fuel levels in both of my TJs.

 

[Gollywomper]

Sounds perfectly normal and consistent with how my gauge indicated fuel levels in both of my TJs.

Did you every try to replace the fuel level senders? I may just cut the vent tube to get 19 gallons in there. I have never been able to put more that 13 in my tank. Even when running it out of fuel, on purpose.

 

[Gollywomper]

Having only about a 10 gallon window between full and the light coming on is annoying. The fuel
Light bugs me.

 

[Jerry Bransford]

Did you every try to replace the fuel level senders? I may just cut the vent tube to get 19 gallons in there. I have never been able to put more that 13 in my tank. Even when running it out of fuel, on purpose.

I changed the fuel pump several times in both Jeeps and none of the attached fuel senders were any more accurate than what they replaced.

 

[Gollywomper]

I changed the fuel pump several times in both Jeeps and none of the attached fuel senders were any more accurate than what they replaced.

Ya I just saw the mopar level sending unit and got my hopes up. I will keep my eyes open for a 19 gal tank. If I can’t find one reasonable then I will mod my tank when it gets pulled for a skid plate.

 

[Jerry Bransford]

Ya I just saw the mopar level sending unit and got my hopes up. I will keep my eyes open for a 19 gal tank. If I can’t find one reasonable then I will mod my tank when it gets pulled for a skid plate.

I'd do the mod since it's nothing more than cutting/shortening the vent tube. Few TJs actually received a 12 gallon tank, most were 19 gallon tanks with a longer vent hose to prevent it from holding more than 12 gallons.

 

[Gollywomper]

It also sounds like the 15 and 19 gallon fuel pump assemblies are interchangeable.

 

[TJ4Jim]

Ya I just saw the mopar level sending unit and got my hopes up. I will keep my eyes open for a 19 gal tank. If I can’t find one reasonable then I will mod my tank when it gets pulled for a skid plate.

As Jerry stated the mod is no big deal, a sharp utility knife and 20 seconds to cut the vent tube back to the tank wall and your done.

Yes the pumps are interchangeable.

 

[Jerry Bransford]

It also sounds like the 15 and 19 gallon fuel pump assemblies are interchangeable.

I can't say for sure but the several I have installed were all spring loaded so that seems reasonable.

 

[Gollywomper]

As Jerry stated the mod is no big deal, a sharp utility knife and 20 seconds to cut the vent tube back to the tank wall and your done.

Yes the pumps are interchangeable.

Yup will do next time the tank comes down. It just seems odd that we can’t get the fuel levels to read correctly. I will also clean the contacts on the level sensor as they can get a film on them that throws off the level too.

 

[Jerry Bransford]

Yup will do next time the tank comes down. It just seems odd that we can’t get the fuel levels to read correctly.

I use the trip odometer to give me a more accurate indication of where I am on the tank level. I use the gas gauge as nothing more than a Full, about half-full, and getting near where I need to think about filling up.