Pioneer Valve Stem Seals

Pioneer offers a complete line of valve seals, from stock O-rings to positive stop Teflon® or Viton® seals. These seals are a must to keep unwanted oil from entering the combustion chamber through the clearance in the valve guides. The O-ring seals use the standard retainer and oil splash shield. The umbrella seals are normally used when a larger-than-stock diameter spring is used. In the case of a double spring, the positive stop Teflon® seals are used. For triple-spring applications, use the smaller-diameter Viton® seals