15-20 Gallon Fuel Tank Slosh Box Warped

Flyer58

Flyer58

YJ Enthusiast
Joined
Apr 12, 2020
Messages
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Location
Magnolia, Texas
I've had a problem with my fuel gauge sticking in different places and have read about the poly slosh box inside the OEM gas tank warping which causes the sending unit float arm to rub or get hung up. I had previously tested the gauge and it works as it should so the problem is at the other end at the tank.

I dropped the tank yesterday along this about 50 lbs of dirt on top and in the skid pan. Removed the fuel pump and sure enough found the slosh tank is warped along the long sides. The pump and sending unit look good and the sending unit tested ohm check was good using a multi meter so this probably confirms the float arm is hitting and hanging up on the box.

So my question is... Has anyone tried folding over a length of sheet metal as a stiffening support on the sides of that slosh box to keep them straight? Should be a simple fix. Any other ideas? This is just a weekend driver on paved roads so no need to go with a $500 new HD tank.

I did do the 15 to 20 gallon mod by cutting the vent tube down to 3 inches or so.

Thanks.

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I’ve heard some people rivet sheet metal to the sides or fold up a box and rivet the panels together where they meet, and then slip that over the slosh bucket.

MTS is the only company making a replacement tank, and is probably the $500 one you’re referring to, it is listed in the 400’s at many vendors. However I got one for pretty cheap from Gas Tank Depot. Was in the 200’s range somewhere I believe.
 
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I have also heard that some people just remove it, I'd be concerned about damaging the tank.
Had to replace my tank anyway, had a 10" crack at half tank.
I bought an OMIX for about $350 and it didn't have a slosh box but did have a molded sump.
Just future reference for anyone who might be interested.
 
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jeepjoe43 said:
I have also heard that some people just remove it, I'd be concerned about damaging the tank.
Had to replace my tank anyway, had a 10" crack at half tank.
I bought an OMIX for about $350 and it didn't have a slosh box but did have a molded sump.
Just future reference for anyone who might be interested.
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FYI, Omix and Crown are both rebranded MTS. Seems like a good design. I wish the molded sump was a bit deeper but hopefully it should be no issue.

Did you have issues getting it bolted under the straps? I ended up getting the skid plate that works properly with it (Warrior sold by MTS) which added some unfortunate cost.
 
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Thanks, other than a coating of dust and mud my tank looks very clean and almost new as does the pump. The skid pan is a different story with lots of rust. I think just to keep the costs down I'll try making a support for the walls, plus I already have several square feet of sheet metal.
 
YES, yes I did have issues getting it bolted back in.
Came in a broken box, so no straps that it was supposed to have.
Had to extend the stock ones, and then the war started.
I was getting I bit pissy after the fourth attempt, and out came the sledgehammer to the skid plate, I WON.
I swear this girl is a sadist..I give her love she gives me grief, beat her and she purrs.
 
jeepjoe43 said:
YES, yes I did have issues getting it bolted back in.
Came in a broken box, so no straps that it was supposed to have.
Had to extend the stock ones, and then the war started.
I was getting I bit pissy after the fourth attempt, and out came the sledgehammer to the skid plate, I WON.
I swear this girl is a sadist..I give her love she gives me grief, beat her and she purrs.
Click to expand...
Don’t worry, you would have had issues with the straps too if they would have been included. For some reason the warrior skid is deeper than most. MTS designed their tank to fit perfectly in a warrior skid with their straps. In the stock skid it never works, or at least I have not seen one person say theirs worked. Thankfully the skid was something I wanted anyways, so I had no real issues forking over the money to make everything happy.

HOWEVER, the warrior skid placed my tank further over to the passenger side by like an inch or two, I had to buy 4” longer hoses from eBay and cut the hell out of them to make them fit. Stock hoses were too short after the skid moved them over. What a mess that was to figure out.
 
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I got lucky on that one, the replacement factory fillers were OK, even after the 1" body lift (While I had it on the lift).
In fact, that's the only part that went smooth.
Would have gotten the skid too, but I was getting into borrowed time with my buddies lift.
Don't think I could have afforded that much shift, not with my new OEM exhaust system.
 
jeepjoe43 said:
I got lucky on that one, the replacement factory fillers were OK, even after the 1" body lift (While I had it on the lift).
In fact, that's the only part that went smooth.
Would have gotten the skid too, but I was getting into borrowed time with my buddies lift.
Don't think I could have afforded that much shift, not with my new OEM exhaust system.
Click to expand...
It’s not the skid itself but it’s the slots on the skid for the straps. They are moved too far over which indexes the tank a bit over. So the tank is closer to exhaust but skid is still in same place so it works. Except the hoses don’t work, so it was a beating. Oh well, got it fixed.
 
Flyer58 said:
One more question about the 20 gallon mod, is there a way to adjust the fuel sending arm to get the full tank range?
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No, as far as I know it’s the same unit for both 15 and 20 or it’s at least very close. My pals with factory 20 gallon tanks said they stayed on Full for 75 or so miles just like all the 15 to 20 gallon conversion owners do. My sending unit did have a 15 gallon sticker on it so maybe there were two different parts but they both performed similarly on 20 gallon capacities. I have never seen an OEM 20 gallon sending unit so I can’t say if they had a sticker that said that on them.
 
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Well no pics of my slosh box fix but I did end up folding over a 4in x 6in piece of stainless steel sheet metal and pressing it down over the wall by the sending arm. Very tight fit which I couldn't pull off so I passed on the pop rivets to hold it in place. I did some measuring first and the arm now clears the side. I also verified it by plugging connecting it to the harness and tilting the tank while watching the gauge. I can hear the arm bouncing pack and forth and see the gauge goes full scale each way.

I also bought a new skid pan off eBay which is slightly thicker than the OEM one. It's mostly dimensionally correct but I needed to bend the side to center the tank and front and back walls so the exhaust clamp fitting clears. Also it's almost 1/2in deeper so on my first try at installing it I found the filler necks are sitting on the frame. A little more tweaking and I'll get it to work.

Here's a few pic's of the 15-20 gal. conversion vent tube I cut and reinstalled. I reached inside with a small hammer and pounded the tube out enough to where I could grab it with pliers. I think I installed a 3 or 4 inch section back in.

vt1.jpg



vt2.jpg
VT3.jpg
 
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