The Hartzell ALY8520R is a belt‑driven 12 V / 60 A aircraft alternator designed to replace older OEM units such as the ALY‑8420 and is commonly used on piston aircraft electrical systems. It is an overhauled unit built to meet or exceed original performance standards, ensuring reliable electrical power for avionics, lighting, starters, and electrical accessories.

Key features:

12 V / 60 A output — supplies stable electrical current to aircraft systems. 
Belt‑driven configuration — includes pulley and cooling fan, so it mounts via a V‑belt on the engine. 
Overhauled by Hartzell/Plane‑Power — tested and restored to like‑new condition, often with core exchange program. 
Direct replacement for legacy belt‑driven alternators on aircraft like Lycoming‑powered models where that alternator spec is required. 
This alternator provides reliable charging of battery and electrical systems across typical general aviation operational ranges and is designed for durable, long‑term service in aircraft environments.