Description
Manufactured by Schaeffler Group, the INA Engine Valve Rocker Arm & Hydraulic Lifter Kit delivers an all-in-one replacement solution designed to restore precise valve lift, eliminate valvetrain chatter, and maximize engine operational efficiency. Serving as the critical transfer mechanism between the camshaft and valve stems, this precision kit pairs low-friction roller rocker arms with auto-adjusting hydraulic lash adjusters (HLA / lifters). Engineered to maintain continuous zero valve clearance under all thermal and operating conditions, INA utilizes high-grade stamped steel or forged aluminum rockers combined with ultra-durable needle roller bearings. By reducing internal valvetrain friction and optimizing hydraulic oil pressure delivery, this kit resolves ticking noises, premature lobe wear, and misfires caused by collapsed lifters. It is the definitive OE-grade service kit for machine shops, professional mechanics, and automotive parts distributors servicing modern overhead camshaft (OHC/DOHC) engines.
Technical Parameters
| Category | Specifications & Technical Details |
| Automatic Hydraulic Lash Adjustment & Zero-Clearance Compensation | The hydraulic lifter / tappet incorporates a high-precision one-way ball valve and high-pressure plunger internally, utilizing engine oil pressure to automatically compensate for valvetrain clearance caused by thermal expansion and contraction or component wear. Maintains zero-clearance valve operation under all operating conditions, fundamentally eliminating metallic ticking noise from valve lash impact. |
| Needle Bearing Roller Rocker Arm & Low Friction Loss | The rocker arm cam contact end utilizes a low-friction needle roller bearing structure, replacing traditional sliding friction pads. The roller converts sliding friction with the camshaft lobe into rolling friction, greatly reducing parasitic friction resistance in the valvetrain and improving engine fuel economy and high-RPM response. |
| 1–3 μm Ultra-Precision Plunger Clearance | The internal plunger-to-sleeve fit tolerance of the hydraulic lifter is refined to micron level (1–3 μm), ensuring extremely low oil leakage rate from the internal high-pressure chamber under extremely high oil temperatures and high-frequency compression. This maintains continuous and stable valve support force, preventing lifter pressure loss and collapse. |
| High-Strength Stamped / Forged Steel Construction | The rocker arm body is manufactured from high-strength stamped steel or heat-treated forged alloy, undergoing carburizing, quenching, or nitriding treatment. It possesses extremely high bending fatigue resistance, capable of withstanding reaction forces and impacts generated by valve springs at high RPM, preventing rocker arm cracking or roller axle detachment. |
| Optimized Internal Oil Passages & Hardened Valve Tip Pad | Precision metered oil passages are designed inside both the rocker arm and lifter, not only providing ample lubrication for the needle roller bearing and lifter cavity, but also spraying an oil film onto the valve stem tip and cam contact surface. The valve stem contact end undergoes ultra-hard polishing treatment, effectively preventing dimpling and abnormal wear at the valve stem tip. |
Applicable Car Brands & Models
Replacing both components simultaneously is strongly advised. Worn hydraulic lifters often cause uneven contact angle and pressure on the rocker arm, while a damaged rocker roller can score a new lifter or camshaft lobe. Installing a full INA kit ensures balanced contact geometry, eliminates uneven wear patterns, and prevents premature valvetrain failure.
A metallic ticking or tapping noise from under the valve cover is typically caused by a collapsed or clogged hydraulic lifter that can no longer hold oil pressure, creating excessive valve lash. Replacing the worn lifters and rocker arms with an OE-quality INA kit restores zero-clearance operation and immediately eliminates the valvetrain noise.
INA hydraulic lifters are shipped factory-filled with testing fluid or protective oil. While soaking them in clean engine oil prior to installation is good practice, they should never be manually compressed or forced empty using tools. Ensure proper engine lube is applied to the contact surfaces, and crank the engine without ignition first to build oil pressure before full startup.
Every INA Rocker Arm & Hydraulic Lifter Kit is sealed in heavy-duty oil-resistant plastic wrap with rust-preventative VCI protection and packaged in protective Schaeffler INA branded boxes. For B2B export orders, individual units are organized in master cartons and palletized with moisture-proof wrapping. MOQs typically start at 10 to 20 kits depending on the specific engine application.
