If the unit is more than 5 years old, I would replace the mechanism package. That is the motor and seals. You have probably impacted some debris in the end of the slide mechanism. You can pull the motor assbly and clean it out, but as I stated, if over 5 years old replace the motor assbly. It is replaced as a unit. Very easy to do after the toilet is pulled. The toilet uses a different flange than a pedal model. You would have to replace the floor mount flange also if changing toilets. Doug
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