A Flexi leash is a retractable leash that has a lock and internal wheel to control the length of the leash. When the leash is retracting, the wheel turns and the leash wraps around it to shorten the leash length. A spring connects the leash to the wheel for tension in winding and unwinding. You can repair or replace a faulty spring inside of a Flexi leash for a minimal amount of money instead of buying a new leash.
Lay the Flexi leash on a flat surface, such as a table. Insert a small Phillips-head screwdriver into each of the two screws by the handle. Turn the screws counterclockwise to loosen and remove them. Set the screws aside.
Insert a small flathead screwdriver into the crack between the two sides of the leash case. The crack is a seam that is in between each half of the leash case. Gently press down on the screwdriver handle to pry the two pieces apart working around in a circle. Lift the top half off the case.
Pull the retractable leash out as far as it will extend and press the lock to hold it in place. Examine the spring that attaches to the leash and the leash case.
Blow any dust particles out with compressed air so the inside is clean.
Remove a broken spring with needle-nose pliers from the leash case and the leash. Place a new spring into the case and bend one end around the leash holder and one end into the slit in the wheel that moves forward and back with the leash wound around it in the case.
Attach a spring that has come loose by bending the loose end onto either the leash holder or in the slit in the leash wheel in the center of the case with needle-nose pliers.
Replace the top half of the leash case, insert the two screws and tighten them clockwise with a Phillips-head screwdriver.
Release the lock and allow the leash to retract into the case.