Leaking Fuel

Ok so I took my cherokee to fill up gas today, well I wasnt watching the pump and somehow I pumped 21gals into my tank before it clicked off. Well My tank is only 20gals and when I noticed it said it was 21 gals I was oh sh** so I look under the jeep. Sure enough theres about 2-3gals of fuel on the ground dripping from the tank. The drip is coming from the top of the tank passenger side. Not the filler side and not from the fuel pump deffinately as I crawled under it and checked. Anyone have any ideas as to what it might be before I drop the tank this weekend? I thought these tanks were sealed but idk.

Specs: 1990 Renix Cherokee No tank skid. Pump is mounted on the side of the tank not the top.

tanks arent sealed..... as you pump fuel out of it, it must be replaced with something (air), there are exceptions to this rule for aviation, but not jeeps.

around these parts, if you had a clogged emmissions hose, you'd know it the minute you failed smog.

is it an aftermarket tank? My 89 pump is mounted to the top/front of the tank. You're saying your pump is on the side????

I think the tank is a "sealed" unit...only the pump and fill hose create "holes" in the tank.

There are vent lines in grommets pressed into the top of the tank (My recollection is that there are two, right and left), and perhaps one of these has cracked, or perhaps overfilling popped it out. It's also not that uncommon for the top of the tank to rust out, since mud and slush come to rest there, but I'd expect a hole big enough to spill that much gas would have given you a gassy smell and leakage for some time. I'm guessing a vent hose off or a grommet popped out.

Flyfisher said:

is it an aftermarket tank? My 89 pump is mounted to the top/front of the tank. You're saying your pump is on the side????

I think the tank is a "sealed" unit...only the pump and fill hose create "holes" in the tank.

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My pump is side mounted from factory, in fact I can change it out without dropping the tank LOL which is a bit nice just have to make sure it isnt full. Ive actually replaced the pump a few times.

Also thanks guys I didnt think about the vent lines. It just kinda alarmed me that a bunch of fuel was dumping on the ground. Now that I think of it I have been smelling a fuel smell a lot lately when the tank is nearly full. Im guessing the seals have just gotten too old. Just looked up the part numbers and will try to get both of them from the jeep dealer tomorrow. Should be an easy fix.

Run the tank empty, drop it(only takes about 15 min.) and look for rust holes or a bad vent/grommet/vac line on top of the tank.

Matthew Currie said:

...gassy smell and leakage...

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Hey...I have that.

Any hoo, I second that. My MJ rollover valves and grommets were rotten and some of the rubber & plastic had fallen into the tank. I found out they were bad after trying to smog it and the smog guy (a friend of mine) nailed it.

sam24th said:

My pump is side mounted from factory, in fact I can change it out without dropping the tank LOL which is a bit nice just have to make sure it isnt full. Ive actually replaced the pump a few times.

Also thanks guys I didnt think about the vent lines. It just kinda alarmed me that a bunch of fuel was dumping on the ground. Now that I think of it I have been smelling a fuel smell a lot lately when the tank is nearly full. Im guessing the seals have just gotten too old. Just looked up the part numbers and will try to get both of them from the jeep dealer tomorrow. Should be an easy fix.

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Don't be too hasty, because if you've been smelling it a while it could be a rust hole. No point in buying parts until you look at it.

I'll be dropping the tank later today after work. Thanks for the help though guys. I suspect the grommet/vent lines though since I have dropped the tank once to change the fuel pump and the tank was perfectly fine. Infact if I think about it the vent line may have came loose when I last dropped the tank to change the pump since the gassy smell started shortly after(same time I pulled the carpet).

Just thought Id update this. Dropped the tank and replaced the valve and grommet today. I swear I am never taking my jeep to another shop again ever for repairs. In case your wondering, (RANT TIME) I replaced the fuel pump in my jeep and it wasnt running correctly (airtex pump) but I was in a hurry so I had a shop replace it a second time instead of doing it myself. The valve and seal were perfectly fine when I did it the first time. Well anyways they replacd it and the second pump didnt work either (airtex again) So I told them to put in a bosche one and it ran ok. But for some unknown reason they went and messed with my TPS so the jeep wasnt running correctly. They said it was a fuel problem and charged me for a fuel pressure regulator. When I got my jeep back it still dint run corectly and I complained. They kept it for 3 weeks after trying to figure it out. I got fed up and told them Im taking my jeep home. They also cut part of my exhaust off cause it got in the way....Sorry I thought I had to rant a bit caused after finding this Im pretty pissed at the shop.

wow... terrible shop service, but it seems youve got it all setup now.

got a part number for that sucka?

XCM, your local dealer should stock the vents/grommets, mine does. They are $15 each +/- and the grommets are around $10 each +/-.

I have replaced the ones on the RENIX XJ and the RENIX MJ. Makes filling the tank up much easier and eliminates that terrible constant gas smell.

sam24th said:

They also cut part of my exhaust off cause it got in the way....

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I would think this would have been illegal if they did not repair the exhaust after the pump R&R. I know it would have been in VA. As a former VA state safety inspector any car that leaves your shop must have the exhaust exiting outside of the pass compartment/cabin. If you have to alter/remove the exhaust for a repair then it must be put back to VA safety standards.

I honestly dont know whats with the laws with the exhaust here in NC. I guess ill find out once I take it for inspection and if it doesnt pass, I guess Tuffy will be seeing me again with a complaint. I really dont want them screwing with my jeep again though. I guess ill jsut have to wait and see. I may make a new post in the SEC Chapt warning others of the shop because honestly those idiots shouldnt even be given wrenches.


As for the mopar part numbers here they are:

The rubber(seal) has a part # of J5360059 which has been superseded by # 52018823 and cost $9.25
The valve(rollover) itself has a part # of J5360058 and cost $11.50

I got these at the dealership and wasnt as bad as I thought it would be.

Ay Ay Ay! Glad you got it un-botched. I won't even try to figure out why they felt they had to cut the exhaust, not to mention the rest.

Again...WOW!. If they cut the exhaust and it got hot enough in that area to MELT that thing, it could have been alot worse...like KA-BOOM...dead!

If you have a Bureau of Automotive Repair (just one of the too many Bureaus in CA) I would report that, send them the picture, and have another shop fix the exhaust and give them the bill...that's just WRONG.