Crankcase Vent 9/16in. Fln.

The K&N Engineering Crankcase Vent 9/16in. Fln. is a purpose-built breather system designed for automotive enthusiasts who demand reliable crankcase pressure management without sacrificing engine bay aesthetics. Whether you're running a stock engine or a heavily modified build, this clamp-on breather prevents pressure buildup that can compromise seals, gaskets, and crankshaft bearings. Proper crankcase ventilation is essential for longevity—it routes blow-by gases away from the engine while maintaining critical pressure balance during all driving conditions.

This half-shielded breather features a robust rubber and steel construction with a 9/16-inch outside diameter tube connection, delivering dependable performance in both street and off-road environments. The design incorporates K&N's signature engineering philosophy: maximum functionality paired with a sleek appearance. The chrome and black finish resists corrosion while the reusable construction allows for easy cleaning and maintenance—no disposable filters to replace. The clamp-on mounting system ensures a secure, vibration-resistant fit without permanent modifications to your engine compartment.

Mechanics and engine builders favor this breather for both naturally aspirated and forced-induction applications where consistent crankcase evacuation prevents oil carryover into the intake tract. Its compact 4 x 2 x 6-inch profile fits tight engine bays, making it ideal for classic restorations, street machines, and competition builds alike. Installation requires only a hose clamp and compatible tubing—verify that your hose inner diameter matches the 9/16-inch fitting before purchase. This single-unit breather integrates seamlessly into custom catch-can systems or direct-to-atmosphere setups, depending on your local emissions regulations and build philosophy.