Wrangler TJ Gas Overflow Fix

Chris said:
The Real Fix

The issue of gas "burping" out of the filler neck right after the pump clicks off when the tank is full is a fairly common issue among Jeep Wrangler TJs. The cause of this is the ethanol in the gas causing plastic parts in the Inlet Check Valve (ICV) to bind and not close quickly enough to prevent fuel back-splash when full.

Owners of 2005 - 2006 TJ Wranglers were left up shit creek by Chrysler and the NHTSA on this one. '07 and newer got a warranty extension (NHTSA closed the investigation taking the heat off Chrysler) '05-'06 owners got the shaft. There's almost no point I filing a complaint with NHTSA any more because our complaints were already dismissed as "Internet hype".

Using the GM hose to address the "fuel spit back" problem is a hack (see below for the "hack" fix). This technique was first posted in the Internet many years ago and has made the rounds enough times in the jeep forums that it has become permanently embedded in the collective knowledge base and won't go away.

The problem is caused by a sticking plastic overflow valve at the inlet to the fuel tank.

The actual fix is is to drop the tank, sand the nubs on the plastic piece in the overflow valve , reassemble the valve then raise the tank back in place. The only "part" required is a piece of sandpaper as shown in the video below.




The Temporary Fix

This is the original "fix" for the fuel spit back problem. While it will usually fix the problem, it is a band-aid at best, and should only be thought of as a temporary fix, whereas the above method is the actual long term fix.

This is how GM fixed the exact same problem in the Trailblazers, Envoys, Bravadas, etc.

Amazon has the replacement part for around $30 here:
http://www.amazon.com/gp/product/B00GUCRISO/?tag=wranglerorg-20

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The bulge in the middle is a little flapper valve:

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Here's our lower hose that connects the filler tube to the tank:

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Here's a how to guide:
The inside diameters are identical. Cut 1 1/4"off the small end and 1 3/4" off the big end. I started out only cutting about 3/4" from the small end to make it the same length as our hose, but it can't make the bend without kinking. I cut some more off and it made for less of a bend and no kink. If you have a body lift, you'll probably need to cut less off. Start small, you can always cut more but once you cut it too short you're on your own...:

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Swap your old clamps onto the GM part:

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The lower clamp has a little clip on it that you put at the top of the hose so you can feel that it's oriented right when you put in on the tank. The round notch on the GM hoseis there to align it with its intended tank, use it as a reference for installing the Jeep clamp. This is very important when it comes to re-installing the new hose. You'll have to feel for this clip because you won't be able to see it clearly:

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That's it!

Reinstall and you're done. I had to remove the 4 torx screws attaching the filler neck to the body to get the new hose on it. I didn't have to disconnect any other lines or take it completely out, but just needed to move the neck around to get the new hose on.


Removal and istallation on a TJ is extremely simple.

Access through lower wheel well cover:

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Loosen the 2 hose clampsand remove the original rubber hose. (1/4" screw clamp upper & 5/16" screw clamp lower) I found it easier to remove the stock hose with the upper filler neck still attached to the body so I could pull down on it.

Cut GM hoseand swap Jeep clamps over (see previous posts).

Remove the 4 torxscrews attaching upper filler pipe to body. You don't have to remove the pipe completely. I didn't even disconnect the tank vent, axle vent, and locker pump lines. You'll only need to move and twist it around a bit to get the new hose on:

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Install modified GM hose, tighten all fasteners, replace trim pieces as necessary - you're done!!!

Note: Make sure the hose is oriented correctly. If the flapper sits crooked or upside down it won't work right. The round notch on the big end of the GM hose before cutting it is for orienting it to its intended tank. You'll have to feel for the little clip on the Jeep hose clamp and make sure it sits at 12 o'clock on the tank inlet.

Here's the installed hose:

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Thanks for the play-by-play. I made the hose switch and it took care of the problem!!!
 
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I completed the "real fix" today, thanks to this thread and that video. I meant to take more pictures, but you know... gas on the hands.

Once I dropped the tank and removed the filler hose, sure enough, the plunger was stuck almost totally closed. That explains why lately I've been having to refuel with an eyedropper. One of the many problems with the People's Republic of Oregonistan is that we're not allowed to fill our own tanks, only the "trained" folks can do that. Of course, they're pretty miffed to have to sit there and hold the refueling handle at a slow speed. I hope they call their congresspeople and complain.

Anyway, pushing the plunger down with a screwdriver, it wasn't totally siezed, but it was sticky at the top and the bottom of its travel. Getting it out was no big deal and after sanding down the nubs it moves very freely. I haven't been to the gas station with it yet. but I dumped a few gallons in by and and it sailed in like I don't remember when.

The biggest part of the job was, of course, the one lonely passenger front skid plate nut. "Of course" because it has the least clearance to get in there with the cut-off wheel, but I made it work. Even split the nut off the bolt without damaging the threads and was able to get another nut on there during re-assembly without much drama.
 
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Before you fixed it, you should have poked a wire down the tube and shoved that plunger to the bottom. Then the highly trained gas station attendants would have gotten gas on their hands every time they filled it up. Something else to complain to their congresspeople about. :p
 
Oh trust me, that has happened plenty of times over the years, depending on where the plunger is stuck. The people at the gas station on the way to the off-road park all know to stand well clear of TJs whilst filling :)
 
My 2003 TJ had a similar issue leaking when tank would get full. Now it leaks a small stream of gas the entire time I'm filling it up. Is my filler hose likely the problem?
 
thejeff said:
My 2003 TJ had a similar issue leaking when tank would get full. Now it leaks a small stream of gas the entire time I'm filling it up. Is my filler hose likely the problem?
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Sounds like it might be split. Get in there with a flashlight and look for it. You may need to squeeze the hose to get it to appear, maybe not since it leaks while filling. Hopefully its not the neck on the tank split or cracked.
 
Got tired of fuel pump issues and overflow so I did this. Take half hour to replace the fuel pump

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Sierra96 said:
Got tired of fuel pump issues and overflow so I did this. Take half hour to replace the fuel pump

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If you're replacing a fuel pump often enough to need to fix it this way, I'd bet you're not fixing the issue (or if you are you're fixing it with the wrong parts).

Fuel pumps shouldn't fail often enough to need regular access.
 
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rasband said:
If you're replacing a fuel pump often enough to need to fix it this way, I'd bet you're not fixing the issue (or if you are you're fixing it with the wrong parts).

Fuel pumps shouldn't fail often enough to need regular access.
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I'm tired of replacing my fuel pump every 100k miles whether I need to or not!
 
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mrblaine said:
Do they make one of those for the right side of the hood so I can change my spark plugs every 30,000 miles. I'm tired and weary of lifting the hood, an access panel would make it so much easier.
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I just do every oil change since I have the hood up anyway...
 
mrblaine said:
Do they make one of those for the right side of the hood so I can change my spark plugs every 30,000 miles. I'm tired and weary of lifting the hood, an access panel would make it so much easier.
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We should also remove those pesky rear inner wheel wells and put access panels there too. This will greatly help with cleaning the mud/debris that gets stuck on the tires when going offroad. Since the we are very clever and have also raptor lined the tub, we can just hose off everything super easy! :ROFLMAO:
 
psrivats said:
We should also remove those pesky rear inner wheel wells and put access panels there too. This will greatly help with cleaning the mud/debris that gets stuck on the tires when going offroad. Since the we are very clever and have also raptor lined the tub, we can just hose off everything super easy! :ROFLMAO:
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But if you get rid of the tub, you won't have to clean it anymore...
 
psrivats said:
We should also remove those pesky rear inner wheel wells and put access panels there too. This will greatly help with cleaning the mud/debris that gets stuck on the tires when going offroad. Since the we are very clever and have also raptor lined the tub, we can just hose off everything super easy! :ROFLMAO:
Click to expand...
 
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