There are three O-rings in a typical Diverter Valve: the valve cover O-ring and two Shaft O-rings. With time these O-rings become brittle and crack. Damaged O-rings on the suction side of the pump will let air into the system. Damaged O-rings on the discharge side of the pump will squirt water. These O-rings should be checked periodically and replaced if necessary. This guide shows you how to inspect and replace your Diverter Valve O-rings.
REPLACE VALVE COVER - Insert the Valve Cover into the Valve Housing. Note that the bottom of the Valve Shaft fits into the hole in the bottom of the Valve Housing. Ensure that the "INLET" label on the Cover is over the common port as noted in Step 6 and push the cover down as far as it will go.
CHECK FOR LEAKS - Look for leaks around the cover and shaft of the diverter valve. If the valve is on the suction side of the pump, spray the top of the valve with soapy water and look for soap bubbles being sucked into a suction leak. If the valve is on the discharge side of the pump, look for water squirting out around the valve cover or shaft.