05K21120 - Lycoming Engines Kit Cylinder with Rings Piston Power Assembly

05K21120 – Lycoming Engines Kit Cylinder with Rings Piston Power Assembly

Available now on the Airparts.aero Marketplace.

Overview

The Lycoming 05K21120 is a genuine Original Equipment Manufacturer (OEM) cylinder power assembly kit, providing a complete, factory-matched solution for replacing a cylinder on the Lycoming O-320-H2AD engine. This engine is famously known as the powerplant for the Cessna 172N Skyhawk, one of the most popular training aircraft ever produced. This is not just a cylinder; it is a comprehensive kit containing all the primary components required to restore the power-producing capability of one cylinder to zero-time, factory-new condition. Featuring a nitrided steel barrel for exceptional durability and including a matched piston, ring set, and all necessary gaskets, this kit is the gold standard for a proper top overhaul.

Key Features

• Nitrided Steel Barrel: The cylinder barrel undergoes a nitriding process, a specialized case-hardening heat treatment. This creates an extremely hard, wear-resistant surface that provides superior protection against corrosion and ensures a longer service life with reduced oil consumption.
• Complete & Matched Assembly: This kit includes a brand-new cylinder assembly (with valves, guides, seats, springs, and retainers pre-installed), a perfectly matched piston with piston pin and plugs, and a complete set of piston rings. This factory matching ensures optimal compression, heat transfer, and oil control.
• All-Inclusive Gasket Set: Comes complete with all the necessary gaskets and seals for the installation of one cylinder, including the cylinder base O-ring, rocker cover gasket, intake and exhaust gaskets. This eliminates the hassle of ordering multiple small parts.
• Genuine Lycoming OEM Part: As a genuine factory kit, every component is guaranteed to meet the stringent material, manufacturing, and quality control standards of Lycoming's FAA Production Certificate. This is the only way to ensure the part conforms to the engine's original Type Certificate.
• Ready for Installation: The kit is delivered ready for a certified mechanic to perform the final piston ring gapping and assembly, significantly reducing the labor and complexity compared to overhauling an old cylinder.

Technical Specifications

• Part Number: 05K21120
• Component Type: Cylinder Power Assembly Kit
• Cylinder Barrel Type: Nitrided Steel
• Kit Contents:
  • 1x Complete Cylinder Assembly (Valves, Guides, Seats, Springs Installed)
  • 1x Piston
  • 1x Piston Pin & Plugs
  • 1x Piston Ring Set (Compression and Oil Control Rings)
  • 1x Gasket Kit (for one cylinder)
• Certification: FAA Production Approval

Aircraft Compatibility

The 05K21120 kit is the specified replacement for the Lycoming O-320-H2AD engine, which was used extensively in one of the world's most popular aircraft.

• Primary Engine Model:
  • Lycoming O-320-H2AD
• Primary Aircraft Platform:
  • Cessna 172N Skyhawk

Applications

The 05K21120 kit is the premier solution for critical engine maintenance on the O-320-H2AD:

• Top Overhaul: The ideal choice when low compression, high oil consumption, or internal corrosion necessitates the replacement of one or more cylinders.
• Engine Overhaul: The foundation of a "new limits" engine overhaul, ensuring all power-producing components are brand new.
• Addressing Engine Issues: A direct solution for addressing issues specific to the H2AD engine, providing the latest factory components.

Why Choose 05K21120?

The health of an engine is determined by the integrity of its cylinders. Using a complete, factory-matched Lycoming kit like the 05K21120 is the single best way to guarantee performance and reliability, especially for an engine model like the O-320-H2AD which has specific operational characteristics. It eliminates the variables and potential compatibility issues of using overhauled cylinders or sourcing individual parts. The nitrided barrel provides a significant durability advantage over older cylinder types, ensuring better long-term value and engine performance. For a component this central to the function and safety of your aircraft, there is no substitute for a genuine Lycoming factory-new kit.

Order Your 05K21120 Cylinder Kit Now

Restore the power, efficiency, and reliability of your engine with a genuine, factory-new cylinder kit from Lycoming. Visit Airparts.aero to order your 05K21120 power assembly kits today.

The nitriding process applied to the Lycoming 05K21120 cylinder barrel is a thermochemical case-hardening process. The steel barrel is heated in a specialized atmosphere containing nitrogen. Nitrogen atoms diffuse into the surface of the steel, forming hard, stable nitride compounds. This creates a "case" on the surface that is significantly harder (often exceeding 65 HRC) than the base steel, providing an exceptionally wear-resistant surface for the piston rings. Unlike chrome plating, nitriding is a diffusion process, not a coating, so it will not flake, peel, or chip. This results in a much faster and more effective break-in period, superior oil retention due to the microscopic porosity of the surface, and a dramatic increase in the cylinder's service life, especially in preventing corrosion pitting.

Note: This is a flight-critical engine component. Installation must be performed by a certified A&P mechanic in strict accordance with the current Lycoming Overhaul Manual and relevant Service Instructions. Proper break-in procedures must be followed after installation to ensure correct seating of the new piston rings.

Cylinder Kits Include

• Intake and exhaust valves, springs, seats, keys and caps
• Piston
• Rings
• Piston pin and plugs
• Rocker shaft cover gasket (angle head)
• Shroud tube seals, cylinder base seal
• Rocker box cover gasket
• Intake and exhaust gaskets

Eligibilities:

Technical Specifications:

• Material: High-strength alloy
• Type: Cylinder Piston/Ring Assembly Kit
• Compliance: Meets FAA and Lycoming specifications
• Application: Designed for use in Lycoming aircraft engines

Key Features:

• High Performance: Provides superior performance and durability, ensuring optimal engine operation.
• Durable Construction: Built with high-strength alloy materials for enhanced durability and long-lasting performance.
• Precision Engineering: Manufactured to exact specifications for a precise fit and reliable operation in Lycoming engines.

Benefits:

• Enhanced Engine Performance: Ensures smooth and efficient engine operation, improving overall performance and fuel efficiency.
• Reliable Operation: Engineered for consistent and dependable performance, reducing the risk of engine failures and maintenance needs.
• Compliance: Meets strict FAA and Lycoming specifications, ensuring high quality and adherence to aviation safety standards.

Applications:

• Aircraft Engines: Ideal for use in Lycoming aircraft engines, providing reliable and efficient performance.
• Engine Maintenance: Suitable for routine maintenance and replacement to ensure optimal engine performance and longevity.

Why Choose Lycoming Engines - Kit Cylinder Piston/Ring Assembly (05K21120)?

The Lycoming Engines Kit Cylinder Piston/Ring Assembly 05K21120 is designed to deliver exceptional performance and reliability for aircraft engines. Its compliance with FAA and Lycoming specifications, along with its durable construction, makes it an essential component for maintaining and enhancing engine performance and safety.

AirParts stocks thousands of engine and engine overhaul parts. Cranks, cases, cams, cylinders, and more. Most available on exchange programs.

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