HOW TO: fix the KJ fuel burp plague!

[profdlp]

It's supposed to get to almost 50F here by midweek. If I get ambitious I might try this then. I sure would like to have this solved. Depends on some other calls I'm expecting, though.

 

[nullptr]

Just did it on my '05. A couple of things came up while doing it that I think others may like to know.

• WD40 sprayed into the hose makes sliding both the valve, and the hose back onto the gas tank, much easier
• Do not over-tighten the clamp over the valve, just snug works. You'll want to make sure the flapper still moves freely.

Now to clean up and head out to a gas station and dinner. :gr_grin:

Thanks for the writeup, ol-flattop!

Edit: Works perfectly! The only downside was not being able to pump at full speed, as that would cause it to shut off. Makes sense, since there is now a slight restriction in the line. However, it shut off perfectly without doing any of the burping. This fixes the problem and is stupid simple, short of the half hour I spent trying to get that stupid filler hose off, to do. If you have the fuel burp issue, order the part and the rivet kit, it's worth taking the time to do.

 

[spta97]

First, thank you for this thread. Now a couple comments:

1) Has everyone who installed this had an issue with not being able to pump at full speed? If so, is it possible to take the existing valve out or replace the hose assembly with a new OEM hose?

2) Any concerns with the longevity of the GM part?

 

[nullptr]

First, thank you for this thread. Now a couple comments:

1) Has everyone who installed this had an issue with not being able to pump at full speed? If so, is it possible to take the existing valve out or replace the hose assembly with a new OEM hose?

2) Any concerns with the longevity of the GM part?

Yes, I can pump at between 1/2 to 3/4 speed. Full speed causes the shutoff to trigger. I suspect this is because the new valve is causing a restriction in the hose. A different, larger, valve would probably not have this problem but would require cutting the hose.

The part itself isn't much more than a plastic cylinder with a metal rod through part of it, and a plastic flapper attached to the rod. It's not in an area it's likely to get banged on, so it should last quite a while. I believe the part is actually GMs answer to a similar issue on their vehicles, and shouldn't suffer from the same 'swollen rubber gasket' problem as it doesn't have one.

 

[ol-flattop]

First, thank you for this thread. Now a couple comments:

1) Has everyone who installed this had an issue with not being able to pump at full speed? If so, is it possible to take the existing valve out or replace the hose assembly with a new OEM hose?

2) Any concerns with the longevity of the GM part?

I've had no issues with auto-shutoff, even on pumps with huge flow rates. I'm fact, my only issue has been that sometimes, when the flow rate is really high, there has occasionally been a small burp as the tank reaches capacity. It's rare, and unless I notice the meter going extraordinarily quickly, I just start the pump and let it go all the way to auto-shutoff, which only occurs when the tank is full.

Null covered the longevity concerns. I have no worries, it's too simple to fail in ordinary circumstances.

 

[bovine]

I just did this fix to my 2006 Liberty and it definitely fixed the overflow problem. I didn't notice any problems refueling at full speed at the Costco fuel pumps either.

I too had difficulty removing the hose from the bottom of the filler spout. Maybe it's possible Jeep might actually have used some type of adhesive or sealant around that connection, in addition to the hose clamp? I ended up inserting a flat screwdriver around the inside of the hose to help break loose its connection to the filler spout prior to pulling it off.

I initially tried to simplify the install by fitting the GM flapper valve in the top end of the Jeep filler hose, but the inner diameter of the hose there is too narrow there. Removing the hose entirely and inserting the flapper at the lower end of the hose as the OP described was indeed the best option.

To help ease the re-install of the hose on the fittings, I sparingly applied a little bit of liquid dish soap.

Here's a video of the overflow problem before the fix: https://www.youtube.com/watch?v=E57ThoqKTzw After the fix, it stops as expected without any problem.

 

[nohitter64]

Gents, I have the parts and am ready to go. One question for clarification. In Step 11 of the OP, what exactly are you marking?

 

[ol-flattop]

Gents, I have the parts and am ready to go. One question for clarification. In Step 11 of the OP, what exactly are you marking?

Sorry about the delay, I’ve been on a road trip and just haven’t had any spare time. Now that I’ve got a chance though, I’m glad to help!

I marked the top of the filler hose, as it sits when connected to the tank. You have to twist the hose a bit to access the open end and insert the flapper valve, so it can be a bit tough to tell where the true top is. In case you’re just not seeing the mark in the picture, try playing with your brightness and contrast. It’s a little tough to see, I admit.

The purpose of this is to give a reference for properly orienting the flapper valve in the tube. If you get it a few degrees off, it won’t make any difference, but if you get it too far to either side, gravity won’t bias the valve toward closing, and the backrush of fuel will likely not close the valve, so the belching problem won’t go away.

I hope this helps! I’ll be happy to answer any other questions. Good luck with the fix!

 

[nohitter64]

Thanks flattop. I'll let you know how it works out.

Sent from my SM-G900V using Tapatalk

 

[ol-flattop]

I just did this fix to my 2006 Liberty and it definitely fixed the overflow problem. I didn't notice any problems refueling at full speed at the Costco fuel pumps either.

I too had difficulty removing the hose from the bottom of the filler spout. Maybe it's possible Jeep might actually have used some type of adhesive or sealant around that connection, in addition to the hose clamp? I ended up inserting a flat screwdriver around the inside of the hose to help break loose its connection to the filler spout prior to pulling it off.

I initially tried to simplify the install by fitting the GM flapper valve in the top end of the Jeep filler hose, but the inner diameter of the hose there is too narrow there. Removing the hose entirely and inserting the flapper at the lower end of the hose as the OP described was indeed the best option.

To help ease the re-install of the hose on the fittings, I sparingly applied a little bit of liquid dish soap.

Here's a video of the overflow problem before the fix: https://www.youtube.com/watch?v=E57ThoqKTzw After the fix, it stops as expected without any problem.

Thanks for your input! I'm thrilled that my work is helping people out.:High 5:

In regards to the dish soap, while it's a good idea for a lubricant, and I did see the word 'sparingly', I wouldn't recommend others do this. When I consider that dish soap is used to clean oil off of waterfowl, it makes it seem like a bad idea to put it into lasting contact with any petroleum product I don't want to ruin. In this case, I'm sure that the regular flow of gasoline through the valve will help prevent the excess from causing issues, but as for the small amount that's actually stuck between the valve housing and the hose...well, I doubt it will be a problem, but I still wouldn't recommend it. WD-40 is a better option, especially since it loses its lubricity as its solvents evaporate, leaving a good, tight interference fit between valve and hose, with no lingering lubricant in between. Frankly, I wish I'd thought of it myself. :emotions122: There's another tidbit that I'll eventually need to add to the OP.

By the way, since working out this fix, I've relocated to a city where ethanol-free gasoline is available at just about every fuel station, and that's what I've been feeding my jeep. Contrast that to my last home, where an ethanol-free gas pump couldn't be found within a 2-hour radius! I'm seriously tempted to order another hose from mopar, switch it out for my current one (which incorporates the flapper valve), and see what happens! It might help to indicate whether this issue is from chronic or acute ethanol exposure. Currently, the few accounts I've seen are divided on this point, so I'm looking forward to putting it to the test. It's pretty far down on the to-do list, but I'll be sure to post results if I ever get to it.

 

[profdlp]

...By the way, since working out this fix, I've relocated to a city where ethanol-free gasoline is available at just about every fuel station, and that's what I've been feeding my jeep. Contrast that to my last home, where an ethanol-free gas pump couldn't be found within a 2-hour radius! I'm seriously tempted to order another hose from mopar, switch it out for my current one (which incorporates the flapper valve), and see what happens! It might help to indicate whether this issue is from chronic or acute ethanol exposure. Currently, the few accounts I've seen are divided on this point, so I'm looking forward to putting it to the test...

Just to add to the speculation about the ethanol, back in Ohio I was able to find some ethanol-free gas here and there. Not always, but sometimes. Since relocating here to the D.C. suburbs I can't find it anywhere. The burp issue seemed to have gotten much worse here.

About a six weeks ago my engine seemed to be acting a little weird and on a whim I started adding Marvel Mystery Oil with every fill-up. (4oz per every 10 gallons, as recommended.) Oddly enough, I have not had one single instance of the fuel burp problem for about a month now. I have been driving a lot this summer and am filling up about every 5-6 days. I didn't turn to the Marvel Mystery Oil to solve the fuel burp problem, but it does seem to have the added side benefit of alleviating it. If it is indeed the reason for the improvement I'm guessing that it counteracts the effect of the ethanol on the (supposedly) one-way valve in the hose.

I wouldn't consider this a real "fix" - I think the method you describe here is the way to ultimately solve this - but for anyone who might care to experiment, it might prove interesting to see if the MMO helps them too. It took two or three fill-ups for the burping to stop, but it hasn't reoccurred for the last five or six fill-ups in a row - something that has never happened before. This leads me to believe that the quality and/or composition of the gasoline is a big factor in this, and not solely a design flaw in the valve.

(And yes, I agree, a design which doesn't take into account the @#$% gas the government is forcing on us is definitely flawed, just that it's not purely a bad valve design problem. There is a distinction between a valve which never works right and one which doesn't work due to outside factors, albeit ones which should have been foreseeable.)

 

[Tanji]

So what does one do if they have both the fuel burp issue as well as the nozzle clicking for a while right when you start to fill the tank up?

 

[ltd02]

So what does one do if they have both the fuel burp issue as well as the nozzle clicking for a while right when you start to fill the tank up?

Not much of a cure from me. When I got my 05 a couple years ago it would always do the quick shut off several times when I first started pumping. I figured out the position of the nozzle that would avoid this. I also usually guesstimate how much it will take and slow it down at the end. I usually only go to maybe three different stations and the one solved the overflow at the end since their pump is always slow... :emotions34:

 

[Tog]

I had both issues had to drop the tank blew out all lines from the tank to the charcoal filter with compressed air . Problem solved

Sent from my SM-G960F using Tapatalk

 

[Jeremy-WI]

So what does one do if they have both the fuel burp issue as well as the nozzle clicking for a while right when you start to fill the tank up?

Sounds like the valve isn't totally stuck yet as mine was stuck open and I had fuel burp, but if the valve is just slow to open and close you could have those issues

 

[nohitter64]

I had both issues had to drop the tank blew out all lines from the tank to the charcoal filter with compressed air . Problem solved

Sent from my SM-G960F using Tapatalk

Tog, Any more details on how to do this? I plan on dropping the tank soon to swap out the fuel pump.

 

[Charles Fry]

Nice write up, but if you are lazy like me, you can avoid the burp by putting the gas nozzle into the tank upside down and resting it on the fuel door and not using the full blast setting on the pump. Works like a charm. And I didn't have to take the jeep apart.

Hey, I said I was lazy.

 

[Artimus]

Nice write up, but if you are lazy like me, you can avoid the burp by putting the gas nozzle into the tank upside down and resting it on the fuel door and not using the full blast setting on the pump. Works like a charm. And I didn't have to take the jeep apart.

Hey, I said I was lazy.

Nice. I'm lazy too!

Good to see a lazy-fix for those of us. I have a '07 KJ and have just learned to live with the fuel burp. There was only one time where it did really bug me as it was a huge spill but I can live with it.

 

[duderz7]

Since I started filling with ethanol free gas I haven't had an issue plus there's a station around the corner from me that has it.

 

[Jasonmc]

Part 2

8. Now that you have access from the wheelhouse side, you need to get access to the hose’s connection to the fuel tank. If you have a fuel tank skid plate, you’ll have to remove it. This is the first time I’ve been glad my KJ has no skids.

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9. With your access portal opened up, you can attack that hose clamp. In my case, it was seized pretty badly, and I almost wrecked it before addressing the issue. A quick spray of WD-40 fixed that problem nicely, and the clamp loosened right up. You could use a flathead screwdriver, but a 9/32 socket works a whole lot better.
10. Pull the hose off the fuel tank. This was surprisingly difficult on my Jeep. YMMV, but I had to work at it quite a bit to get it to cooperate. The cold contributed, I’m sure, and vacuum pressure might have added to the difficulty before I removed the gas cap, but mostly it was just a hose that had made its home and didn’t want to leave. Eventually it came off the fuel tank mouth. Then pull it through its hole in the frame as well, and you’ve got a nice open area to work on it.

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If you skipped steps 4-7, then instead you have a tiny, cramped area and are lying on your back with a flashlight in your mouth and a sore neck. Yup, hindsight is 20/20.
11. You might be able to get the other end of the hose off the filler tube, but I wasn’t, and it really isn’t necessary or particularly helpful.

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At this point, I marked the top of the tube as a reference for correctly timing my flapper valve. While eyeballing it will probably be just fine, a little extra help can’t hurt.

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12. Now comes the fun part. Make CERTAIN you have the valve positioned to open toward the tank! otherwise, you’ll be unable to fill the tank, and will have to start all over. And you’d feel really dumb doing that, wouldn’t you? Orient the valve with the hinge pin on top so that gravity keeps it shut when held level, and then stuff it up the hose. Others have suggested using a deep well socket the same diameter as the valve housing to drive it in. I didn’t have one that size or close enough on hand, so I ended up using a 6” socket extension. Worked like a charm.

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I just alternated pressing the valve housing at the top and bottom until I got it past the bend in the hose, which is as far as it’s really necessary to go. Use whatever works for you, but that’s how I did it. You’ll want to be careful of a couple things: first, if you use something smaller than the valve housing, you risk the tool slipping off and smashing the flapper valve or its hinge pin. If that happens, it’s game over. Second, if you use something the same size or larger than the valve housing, that means it’s also larger than the hose, and you risk getting it irretrievably stuck in the hose behind the valve! Pick the risk you’d rather manage, then don’t ***** up!

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13. This is probably unnecessary, given the interference fit between valve and hose, but the name of the game here is overkill. Take the hose clamp you salvaged from the GM hose at the beginning, and install it around the valve in the hose. Here you can see the valve’s profile in the hose.

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And now, with the clamp installed.

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When you look up the hose, you should now see this.

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If so, you’re practically done!
14. Thread the hose, with newly installed flapper valve, back through the hole in the frame and onto the fuel tank mouth. Tighten the hose clamp, nice and tight. Don’t just snug it on there, keep going or this connection WILL leak, and paying for fuel as it drips directly onto the ground is kind of what we’re trying to avoid, right? The wrench will tell you when to stop—you’ll notice a SHARP increase in resistance, and then it’s perfect.

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15. Replace the wheelhouse liner. Now you get to use your snazzy new riveter. It’s really easy, and pretty much self-explanatory. One note, however: remember I said the HF rivets were nearly perfect? I stuck in a couple of those rivets with no issues, then had several in a row where the mandrel popped off before the rivet compressed.

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Sure, I remember NOW that I’d read that could happen, and to soak them in water beforehand to avoid that problem. At any rate, when I ran out, I just used some of the bigger ones, and everything’s cool.
16. Replace the wheel, drop the Jeep from its stand, dutifully torque those lug nuts (80-100 ft-lbs, if memory serves), and you’re all done. Yes, I know that my wheels look like **** and that my tires actually are ****. One catastrophe at a time!

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So that’s how I spent my Thanksgiving night. After a year of living in fear of a nasty fuel belch on me or another unsuspecting driver of my jeep, I’d finally done something about it, and was left with a feeling of deep satisfaction. The only thing that could have made it more satisfying would be if the fix had actually worked!































I’m kidding. It worked like a dream. No more spit up. I guess my baby’s growing up. :happy107: Enjoy, folks!

I just did this process on my daughters 06 liberty, and it was a nice relief to let the pump run to the end while not try to listen for the top of the fill approaching, to get the pump turned off before it spewed gas all down the side. I used a plug socket with a 1/4 inch extension fed into it from the opposite side, so I would have a way to pull the socket out if it got stuck