How to Fix a Leaky Check Valve on a Sump Pump

Unplug the sump pump's electrical cord from the outlet. If the sump pump is hardwired, switch the breaker in the breaker box off. Locate the leaky check valve. Place a plastic bucket directly under the valve to catch any water that drains out of the pipe after removal.

Use a hacksaw to cut the leaky check valve above and below the PVC pipe. Cut as close to the check valve as possible. If the check valve uses metal clamps to secure it to the pipe, instead of the pipe fitting inside check valve, skip this step and move on to Step 3.

Remove the screws on the clamps that secure the PVC pipe to the check valve. Lift the old check valve off the pipe.

Insert the discharge pipe in the new check valve. Insert the intake pipe in the other end of the new check valve. There is an arrow located on the check valve that shows you the direction of the water flow. Make sure the arrow is pointed at the drain and not at the sump pump. The pipes must fit securely in the check valve without sliding about.

Brush a liberal amount of PVC cement on the areas of the pipes that connect to the new check valve. Reposition the metal clamps and secure them by tightening the screws with a screwdriver. Use the screwdriver to tighten the screws on the check valve.

Plug the sump pump into the electrical outlet or switch the breaker in the breaker box back on. Add water to the sump pump pit and -- when the sump pump activates -- examine the check valve for leaks.