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  1. #1

    Default Where is the leak?

    Hey all, after patching a hole I found in my tank, it appears there's another leak somewhere as well. When the tank is around 1/2 full, there is no sign of a leak, but after filling it up for the first time since patching the tank, it appears there's another leak somewhere. What's strange is I see no signs of a leak on the upper half of the tank, but there is a fair amount of fuel on the underside plastic.

    It only appears to happen when the vehicle is or has been in motion. I didn't notice a leak while parked and running. Again, the only signs of the leak are on the underside of the tank where the vented plastic is attached to the tank. Any ideas?

    1998 Chevrolet Silverado
    5.7L v8 Vortec
    Dual Flowmaster 40s
    Kenwood stereo and speakers

  2. #2


    Found it! There was a massive hole, roughly 1in in diameter, that had been siliconed over by some repair shop in the past (prior to my ownership). I found a metal fitting, jb welded it into place, and placed a screw in the hole of the fitting. (on the off chance that there was once a pressure tube there).

  3. #3


    That is pretty interesting. Were you able to seal it somehow?

    1995 Silverado 4x4
    6" BDS Suspension Lift-3" Body Lift-Add A Leaf in rear -Trailmaster SSV Shocks-Duel Steering Stabilizer Kit -AirAid Cold air intake-
    4.56 Gears with Detroit Auburn Locker-Pro-Comp Traction Bars with duel shocks-Aluminum Skid Plate Kit-38.5" x 16.5" Mickey Thompson Baja Claws-Constant Dropping fuel gauge

    2005 Yukon XL Jet Power Programmer, Bilstein Shocks, Bilstein rear springs, Helwig Anti-sway bars, EGR Window Visors, EGR Hood Shield, Denali Headlights, Headlight harness upgrade, GE NightHawk Bulbs, White Night Rear lighting system, Russell Braided SS brake lines, PowerStop Brake pads, PowerStop cross drilled and Slotted Rotors,
    2002 Silverado ext cab 2wd (Sold)
    2003 Yukon XL (Totaled)

  4. #4


    Quote Originally Posted by Pikey View Post
    That is pretty interesting. Were you able to seal it somehow?
    Yeah, used a plastic seal and a ton of jb weld. Seems to be holding for now.

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