Alternator Drive Couplings

Overhauled Alternator Drive Coupling - P/N 635796

Designed to connect the alternator to the engine, ensuring reliable power generation for aircraft systems
This drive coupling is engineered for durability and efficiency, featuring a robust construction that includes high-strength aluminum for lightweight yet resilient performance.

Longer service life
Reduced maintenance needs
Consistent, reliable performance in a variety of aviation applications
Alternators and coupling drive tools also available!

Key Features:

Approximately 1.2lbs
Dimensions optimized for compact installation, with torque capacity up to 150lb-ft
Operates effectively within temperature range of -40°F to 250°F
Drive hub features refined coupling geometry that improves alignment and reduces vibration, ensuring a more sable connection between the alternator and the engine
Precision machined components and improved lubrication system that reduces friction and wear
Increased durability and resistance to wear and corrosion

In commercial and military aircraft, the drive coupling ensures stable alternator performance, which is essential for powering avionics and other systems. For recreational aircraft, it enhances engine efficiency and minimizes maintenance by providing a dependable connection. The 635796 drive coupling improves overall engine performance, reduces wear, and ensures consistent power output, making it a key component for reliable operation in diverse aviation environments.

Overhaul Service Includes:

Thorough inspection to identify any wear or damage
Meticulous cleaning to remove contaminants
Replacement of worn or faulty parts with high-quality replacements
Rigorous testing of drive hub to ensure it meets all performance and safety standards

Overhauled Alternator Drive Coupling - P/N 646655

Made for Continental gear-driven alternators
Helps absorb engine vibrations and includes a built-in shear section to protect both the alternator and engine. This elastomer-style coupling replaces older spring-type versions (PN 640933 and 640934) and meets the requirements of Continental Service Bulletin SB11-3.

Suitable for Continental engine models IO/TSIO-520, IFO/TSIOF-550, TSIOL-550, and GTSIO-520
Incorporates an elastomer section to dampen vibrations and provide a fail-safe shear mechanism
Request proper torque application (300-450 in-lbs) and correction orientation of thrust washer (copper-colored side facing the alternator)
Should be inspected for slippage torque; must resist slippage at a minimum of 180 in-lbs, while in service couplings should not drop below 140 in-lbs
Alternators and coupling drive tools also available!

Additional Technical Notes:

Cotter Pin Installation: After torquing the coupling nut, ensure the cotter pin is properly installed. If the slots in the nut do not align with the hole in the shaft, tighten the nut further (without exceeding 450 in-lbs) to achieve alignment. Do not loosen the nut to align the slots, as this can compromise torque integrity.
Alternator Mounting Torque: When installing the alternator onto the engine, torque the mounting nuts to 150–180 in-lbs in a crisscross pattern to ensure even seating.
Woodruff Key Verification: Before installation, verify that the woodruff key is properly installed in the alternator shaft. An improperly seated or missing key can lead to coupling misalignment and potential failure.
Thread Preparation: Clean and, if necessary, lightly lubricate the threads of the coupling nut and shaft to ensure accurate torque readings and prevent galling.
Thrust Washer Reuse: Always use a new thrust washer during installation. Reusing an old washer can lead to improper seating and potential coupling failure.
Shipping Hardware Identification: Be aware that some alternators may be shipped with a metal shipping washer and/or spacer. These components must be removed and discarded before installation, as their presence can cause interference with the engine’s gear train, leading to significant damage. hartzell.aero
Coupling Slippage Testing: When performing the slippage torque test, rotate the coupling at a rate of 1 to 2 degrees per second. This controlled rate ensures accurate measurement of the coupling’s resistance.
Regular Inspection Interval: While Continental recommends inspecting the alternator and coupling every 500 hours, consider performing this inspection during each annual maintenance cycle or whenever the alternator is removed, to ensure ongoing reliability.