Remove the seat complete with it's hinges. Turn it upside down and inside the hinge plates you will notice a 'phillips' screw. Make sure that this is tight, as this could be the problem rather than the wing-nuts'. However, check that the wing nuts (if plastic/nylon) are not split.
You may need to adjust the position of the plates a few times, before fully tightening the screws, to get the seat in the optimum position.
DO NOT over tighten the wing nuts.
RSD
RSD Handyman Services
March 2008
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