Lycoming 17D29057 Inner Valve Spring is a precision-engineered valve train component designed for use in compatible Lycoming aircraft piston engines. This inner valve spring serves as part of the dual spring assembly, working together with the outer valve spring to provide consistent valve control and reliable operation throughout the engine operating range.

The inner valve spring provides additional closing force and support for the valve train, helping maintain proper valve contact, prevent valve float, and ensure accurate valve timing during engine operation. Its function is critical for maintaining efficient combustion, stable engine performance, and reliable cylinder operation.

The 17D29057 spring is an alternative replacement for LW-11797 and is manufactured to meet Lycoming engine requirements. Designed for repeated compression cycles, the spring withstands high temperatures, vibration, and continuous mechanical loading experienced within aircraft piston engines.

The inner valve spring should be inspected during cylinder maintenance and engine overhaul for loss of tension, corrosion, cracking, deformation, or other signs of fatigue. Replacement of worn valve springs helps maintain proper valve train operation and supports continued engine airworthiness.

Key Features

- Part Number: 17D29057
- Manufacturer: Lycoming Engines
- Component: Inner Valve Spring
- Alternative To: LW-11797
- Provides additional closing force within the dual valve spring assembly
- Helps prevent valve float and maintain accurate valve timing
- Designed for high-temperature and high-cycle aircraft engine operation
- Manufactured for reliable spring tension and long service life
- Suitable for compatible Lycoming aircraft engines