Repair a leaking polyvinyl chloride pipe by cutting out the leaking portion of the pipe and using couplings for gluing a new section. If the leak is within 2 inches of an existing fitting, cut away the fitting, and install a new one. There are no practical ways to remove PVC pipes from glue fittings.
Leave the pipe pressurized, and look for the leak. In some cases, water travels a considerable distance along the pipe before enough collects to form a drop. Once you locate the leak, turn off the water, and open a faucet to relieve the pressure. If working inside the home, open a faucet below the leak, if possible, and drain the water, eliminating spills. Cut the pipe with a hacksaw or a PVC tubing cutter, allow any residual water to drain from the remaining pipe, and dry the pipe with a rag.
Cut the replacement pipe to length, and dry fit it and any fittings in place. Apply the primer to the inside of the fitting and outside of the pipe. Once it dries, apply the solvent glue and push the pipe into the fittings. Turn the pipe one-quarter turn to spread the solvent, and allow drying time before repressurizing the pipe.