SL13641 - Superior Air Parts FAA-PMA Magneto Drive Cushion

SL13641 – Superior Air Parts FAA-PMA Magneto Drive Cushion (replaces Lycoming 68H22624)

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The Superior Air Parts SL13641 is a premium, FAA-PMA certified elastomeric damper cushion, engineered as a direct replacement for the Lycoming OEM part number 68H22624. Manufactured by Superior Air Parts, a leader in the FAA-PMA market, this component performs the flight-critical function of absorbing torsional vibrations and shock loads within the magneto drive gear assembly. It acts as an essential flexible coupling, protecting the magneto's high-precision internal components from engine power pulses and the sharp kickback loads generated by the impulse coupling during start-up.

As an FAA-PMA approved part, the SL13641 has undergone a rigorous certification process to demonstrate that its material, design, and performance are equivalent to or superior than the original OEM component. It is precision-molded from an advanced, high-durometer elastomer compound specifically formulated for long-term resistance to heat and oil, providing a dependable and cost-effective solution for engine overhaul and magneto maintenance.

Key Features

• FAA-PMA Approved Replacement: Fully certified by the FAA as a safe and direct replacement for Lycoming P/N 68H22624, ensuring airworthiness and compliance.

• Meets or Exceeds OEM Specifications: Designed and manufactured to the highest standards, ensuring performance and durability that is equivalent or superior to the original component.

• Advanced Elastomer Compound: Utilizes a modern, high-grade synthetic rubber formulated for a long service life and consistent damping properties in a hot oil environment.

• Protects Ignition System Components: Absorbs damaging torsional shocks and impulse coupling kickback, preventing premature wear and failure of the magneto's delicate internal gears and bearings.

• Cost-Effective, High-Quality Alternative: Provides a trusted, reliable, and economical option for replacing a mandatory-replacement wear item during engine maintenance.

Technical Specifications

• Part Number: SL13641

• Component Type: FAA-PMA Magneto Drive Gear Damper Cushion

• Manufacturer: Superior Air Parts, Inc.

• Replaces: Lycoming P/N 68H22624

• Material: High-Durometer, Oil/Heat-Resistant Synthetic Rubber (Elastomer).

• Application: Fits within the magneto drive gear assembly in the engine's accessory case.

Engine Compatibility

The SL13641 is FAA-PMA approved for installation on the vast majority of direct-drive Lycoming engines where the Lycoming P/N 68H22624 is specified. Applicable engine families include, but are not limited to:

• O-235, O-320, IO-320, AEIO-320 Series

• O-360, IO-360, AEIO-360, TIO-360 Series

• O-540, IO-540, AEIO-540, TIO-540, LTIO-540 Series

Crucial Note: The official FAA-PMA supplement for SL13641 and the specific engine's Illustrated Parts Catalog (IPC) are the final authorities for verifying installation eligibility.

Applications

This damper cushion is a critical replacement part during major engine and ignition system maintenance.

• Complete Engine Overhaul

• 500-Hour Magneto Inspection and Repair

• Any maintenance requiring the removal of the magneto and its drive gear assembly.

Why Choose SL13641?

Choosing the Superior Air Parts SL13641 provides a certified, high-quality alternative from a leading and trusted manufacturer of aftermarket components. The FAA-PMA approval guarantees that the part is a safe and reliable substitute, often at a more competitive price point. A hardened, degraded cushion is a primary cause of premature magneto failure. The SL13641 is made from a modern elastomer compound designed for durability, ensuring your engine's ignition system is properly protected from damaging shock loads for its full service interval.

The SL13641 cushion functions as a viscoelastic damper, dissipating mechanical energy through the principle of hysteresis. To gain FAA-PMA approval, it must effectively replicate the damping characteristics of the original part. When a sharp torque is applied to the magneto drive gear, the elastomeric cushion deforms. Part of this deformation energy is stored elastically within the polymer's molecular chains and is returned to the system (like a spring). However, a significant portion of the energy is converted into heat due to the internal friction of these long polymer chains sliding against each other during deformation. This conversion of mechanical shock energy into low-grade thermal energy, which is then dissipated into the engine oil, is known as hysteretic damping. The effectiveness of the damper is a direct function of the material's durometer (a measure of its stiffness) and its damping coefficient. Superior Air Parts has selected a specific elastomer compound with a durometer that is stiff enough to transmit the required drive torque without excessive rotational lag ("wind-up"), yet has a high enough damping coefficient to effectively attenuate the peak shock loads that would otherwise be imparted to the magneto's bearings and impulse coupling components.

Note: This is a flight-critical ignition system component. It is a mandatory replacement item at every engine overhaul and is highly recommended for replacement at every 500-hour magneto inspection, or any time the magneto is removed. A cushion that is found to be hardened, cracked, or swollen is unairworthy and must be replaced. Installation must be performed by a certified A&P mechanic in accordance with the Lycoming overhaul and maintenance manuals.

Documentation

The definitive application and installation eligibility for this FAA-PMA component must be confirmed using the official FAA-PMA database and the Illustrated Parts Catalog (IPC) and maintenance manuals for the specific engine model.