If the oil in your pump turns a milky gray color, you should replace your diaphragms. If you keep using the pump with mixed oil, it will damage or destroy the unit. Before that happens, change out the diaphragms with the 8700.22CK KAPPA-120/150 Complete Diaphragm Repair Kit. It includes everything you need to restore functionality, such as check valve assemblies, o-rings, diaphragm bolts, diaphragm washers, accumulator diaphragm and piston diaphragms.