Different than other seals in the engine, valve stem seals play an important role in lubrication. Valve stem seals allow a controlled amount of oil to lubricate the valve stem as it moves in the valve guide. The amount of oil that passes by the valve stem seal must be precisely controlled. Too little oil causes stem and guide wear; too much oil causes carbon buildup leading to valve seat damage, decrease in volumetric efficiency, increased emissions, catalytic converter degradation and excessive oil consumption. 

QAP supplies Valve stem seals for all conventional passenger car, trucks, forklifts, commercial vehicle, construction vehicle, heavy duty, machine engines. QAP also provides gasket set, gasket kit, manifold gaskets, oil pan gaskets o-rings and other related products. As a head gasket leader in technology, an original equipment manufacturer transfers all of his expertise, experience and quality into the replacement parts business. We are the aftermarket gasket maker for many series of vehicles such as Caterpillar, Perkins, Cummins, Yanmar, Kubota, Honda, Toyota, Suzuki, Komatsu, Hino, Daihatsu, Mitsubishi, Mazda, Nissan, Iveco, Scania……

QAP uses a variety of materials including nylon, PTFE, rubber, steel and synthetic rubber or some combination of these. FKM, fluoroelastomer, is used in many QAP valve stem seals for hotter-running, late-model vehicles. It is often combined with a metal jacket or covering that totally surrounds the FKM positive seal. FKM offers excellent resistance to both heat (up to 450°F) and abrasion.