646238-2 - Hartzell Engine Technologies Starter Assembly

646238-2 – Hartzell Engine Technologies Lightweight Starter Assembly

Available now on the Airparts.aero Marketplace.

Overview

The Hartzell Engine Technologies 646238-2 is a genuine OEM, flight-critical, lightweight starter assembly engineered for a wide range of Lycoming piston engines. This is a state-of-the-art, high-torque starter designed as a direct, superior replacement for older, heavier legacy starter models. Its primary function is to provide the powerful initial rotational force required to crank the engine for starting. Utilizing advanced permanent magnet motor technology, the 646238-2 delivers significantly higher cranking speed with less current draw compared to older designs, resulting in faster, cooler starts which reduces stress on both the engine and the electrical system. As a certified component from a leading OEM, this starter represents the pinnacle of reliability and performance for Lycoming engine applications. 👍

Key Features

• Genuine Hartzell / FAA-PMA Certified: A fully certified, airworthy component from a world leader in engine accessories, ensuring the highest standards of quality and reliability.

• Lightweight Design: Offers a significant weight savings (often several pounds) compared to the legacy starters it replaces, increasing the aircraft's useful load.

• High-Torque Permanent Magnet Motor: Delivers superior cranking torque and speed for faster, cooler starts, reducing engine wear and the risk of kickback.

• Reduced Current Draw: More efficient motor technology draws less current from the battery, preserving battery life and reducing stress on the electrical system.

• Increased Reliability: Modern design and manufacturing processes result in a starter with enhanced durability and a longer service life compared to older models.

• Direct Replacement: Engineered as a form, fit, and function replacement for numerous legacy Lycoming starter part numbers, ensuring straightforward installation.

Technical Specifications

• Part Number: 646238-2

• Component Type: Lightweight Engine Starter Assembly

• OEM Manufacturer: Hartzell Engine Technologies

• Voltage Rating: 12 VDC (for 14V nominal systems) or 24 VDC (for 28V nominal systems) - Verify specific P/N configuration for voltage.

• Motor Technology: Permanent Magnet DC

• Drive Type: Direct Drive (interfaces with engine ring gear)

• Weight: Significantly lighter than legacy models (e.g., ~7-9 lbs range).

• Certifications: FAA-PMA

Aircraft Compatibility

This starter assembly is specified as a direct replacement on a vast range of aircraft powered by Lycoming engines, including but not limited to:

• Engine Series: O-235, O-320, IO-320, O-360, IO-360, AEIO-360, O-540, IO-540 series.

• Common Aircraft Applications:

  • Cessna 172

  • Piper PA-28 (Cherokee, Warrior, Archer, Arrow), PA-32 (Cherokee Six, Saratoga)

  • Beechcraft Musketeer, Sundowner, Sierra

  • Mooney M20 series

  • Grumman American AA-5 series

  • Many experimental and kit aircraft using these Lycoming engines.

Note: This is a flight-critical engine component. The specific engine Illustrated Parts Catalog (IPC) or STC data is the final and absolute authority for determining part applicability.

Applications

• Primary Engine Starting: Provides the mechanical torque to rotate the engine crankshaft for starting.

• Direct Replacement/Upgrade: Replaces older, heavier, or less reliable original equipment starters (e.g., Prestolite, Kelly Aerospace).

Why Choose 646238-2?

Reliable engine starting is non-negotiable. The Hartzell 646238-2 offers a significant upgrade in both performance and reliability over legacy starters. Its high-torque motor spins the engine faster, leading to quicker starts with less stress on engine components and reduced risk of kickback or hot starts. The weight savings directly translates to increased payload. As a fully certified, modern starter from a trusted OEM, it eliminates the uncertainty associated with older designs or improperly overhauled units. For a faster start, longer life, and certified safety, the Hartzell lightweight starter is the clear choice. ✈️

The engineering advantage of the 646238-2's permanent magnet motor lies in its efficiency and torque characteristics. Traditional aircraft starters often use series-wound DC motors, which create their magnetic field via heavy copper field coils. These coils consume significant current and generate heat. A permanent magnet motor replaces these field coils with high-energy rare-earth magnets (like Neodymium). This eliminates the current draw needed for the field, making the motor much more efficient and lighter. Furthermore, permanent magnet motors develop very high torque instantly upon application of power (high torque at zero RPM), which is exactly what's needed to overcome the engine's static inertia and compression, resulting in faster breakaway and quicker acceleration to a self-sustaining engine speed.

Note: The 646238-2 is a flight-critical engine component. Installation must be performed by a certified A&P/IA mechanic in strict accordance with the Hartzell installation instructions and the aircraft/engine maintenance manual. Ensure the battery is disconnected before removal or installation. All electrical connections must be clean, secure, and torqued to the specified values to handle the high starting current.

Documentation

• Hartzell Engine Technologies Website: Full application charts, cross-reference guides, installation instructions, and technical documents for Hartzell starters are publicly available for download from the official HET website.

Description:   Starter Assembly - Overhauled
Part Number:   ES646238-2R
Alternate Part Number:   ES646238-2, 646238-2
OEM:   Continental
OEM Part number:   646238-2
FAA Eligibiity:   [ Click here ]

Fits in Aircraft Engine model:

Related Documents:

Application Guide:   [ Click here ]
Service Information Letter:   [ Click here ]
ES646 Service Parts:   [ Click here ]

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