This invention relates to an improved check valve for use in a power brake system.

In modern cars, because of the Federal Highway Safety Standard requirements, all engines are equipped with smog devices to reduce air pollution. Check ValvesIn tuning such an engine to operate at a level of efficiency and because of added components, such as air conditioning, the temperature under the hood has risen considerably in the past few years. This is especially noted upon restarting a recently stopped engine because the cooling system does not operate to carry away any heat. CHECK VALVESIf the valves of the vehicle are not tuned properly with this increase in under the hood temperature, it is possible for fuel vapor to enter the piston chamber when the engine is stopped.Check Valves Now upon restarting, it is possible that the engine may backfire through the manifold causing a high internal back pressure in the vacuum system. A one-way plastic check valve in the brake system prevents this back pressure from causing damage to the power booster. These plastic check valves are constructed of two pieces which snap together, but due to heat expansion and a sudden surge of back pressure snap apart, also causing a loss of vacuum power assist in the braking system.

MORE NEW