Lycoming 17F21185 Rocker Assembly is a precision-engineered valve train component designed for use in compatible Lycoming aircraft piston engines. This rocker assembly replaces the previous 67112 part number and provides the mechanical linkage required to transfer movement from the pushrod assembly to the engine valve.

The rocker assembly operates as a pivoting mechanism within the valve train, converting pushrod movement into controlled valve opening and closing action. Proper rocker function is essential for maintaining accurate valve timing, correct valve lift, and efficient intake and exhaust flow during engine operation.

Manufactured to Lycoming specifications, the 17F21185 rocker assembly is designed to withstand continuous mechanical loads, vibration, lubrication exposure, and elevated temperatures found in aircraft piston engines. Precision-machined surfaces help ensure smooth operation, proper alignment, and reduced wear within the valve train system.

The rocker assembly should be inspected during cylinder maintenance and engine overhaul procedures for signs of wear, excessive clearance, damaged contact surfaces, or abnormal movement. Replacing worn rocker components helps maintain proper valve train performance and supports continued engine reliability.

Key Features

- Part Number: 17F21185
- Manufacturer: Lycoming Engines
- Component: Rocker Assembly
- Replacement For: 67112
- Transfers motion between the pushrod and engine valve
- Supports accurate valve timing and valve operation
- Precision-manufactured for correct fit and reliable movement
- Designed to withstand vibration, lubrication, and cyclic engine loads
- Suitable for compatible Lycoming aircraft engines