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Overfilling gas tank

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Old Jan 31, 2018 | 08:36 PM
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Default Overfilling gas tank

I was at the gas station tonight and set the pump to fill automatically and it ended up overfilling and fuel burst out of the two black plugs at the bottom of the gas tank. I'm guessing those plugs will burst if they sense too much pressure and vent gas correct? But then reseal when enough fuel has been let out? Can someone explain that or is that all there is to it?
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Old Jan 31, 2018 | 10:25 PM
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Originally Posted by foxrox0620
I was at the gas station tonight and set the pump to fill automatically and it ended up overfilling and fuel burst out of the two black plugs at the bottom of the gas tank. I'm guessing those plugs will burst if they sense too much pressure and vent gas correct? But then reseal when enough fuel has been let out? Can someone explain that or is that all there is to it?
I'm not sure about the plugs but it sounds like the fuel pump failed to cut fuel flow when it sensed back pressure of fuel.
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Old Feb 1, 2018 | 12:08 AM
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What "black plugs"? Nothing at the bottom of the fuel tank is ever supposed to release fuel and then seal back up.
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Old Feb 1, 2018 | 12:38 AM
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I have my tank sitting on the ground right now....only holes in it are the filler neck and the fuel pump opening....where did fuel come out ???
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Old Feb 1, 2018 | 02:42 AM
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Are you sure you aren't looking at the rubber plugs in the bottom of the trunk? The only way I see that happening is if the seal on top of the tank blew and gas was running down the trunk area and happened to drip off the plugs.
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Old Feb 1, 2018 | 06:18 AM
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I could have sworn I saw those two rubber plugs expand, guess it was just too much fuel coming from the top seal draining down, should I drop the tank and put on a new seal or is it not worth it?
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Old Feb 1, 2018 | 12:59 PM
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Are you sure it didn't just spill out the top of the fill neck, run down the side of the tank and spread out from there?

If the top of the tank wasn't sealing properly and leaked badly enough to flow fuel, I'd expect you to get an EVAP code - unless you've disabled those DTCs with a custom tune.
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Old Feb 2, 2018 | 10:39 AM
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Originally Posted by RPM WS6
Are you sure it didn't just spill out the top of the fill neck, run down the side of the tank and spread out from there?

If the top of the tank wasn't sealing properly and leaked badly enough to flow fuel, I'd expect you to get an EVAP code - unless you've disabled those DTCs with a custom tune.
It honestly probably did that and I was just too focused on where the fuel was going. Evap hasn't been tuned out looks like, thanks all for the help.
Attached Thumbnails Overfilling gas tank-evap.jpg  
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Old Feb 2, 2018 | 07:16 PM
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there is a rubber ( ? ) seal under the retaining ring holding the fuel bucket....I guess it could leak.....but that would mean other problems I think
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