ES-4004 - Hartzell Engine Technologies LLC - Alternator 28V/38A

ES-4004 – Hartzell Engine Tech 28V, 38A Belt-Driven Alternator

Available now on the Airparts.aero Marketplace.

Overview

The ES-4004 from Hartzell Engine Technologies is a high-quality, FAA-PMA certified, belt-driven alternator designed as a direct replacement for the original equipment Ford and Prestolite alternators on a wide range of Continental engines. This is a flight-critical component that serves as the primary source of electrical power for an aircraft's 28-volt DC system. With a continuous output rating of 38 amps, it is an ideal, modern solution for light aircraft with standard electrical and avionics loads.

Unlike gear-driven units, the ES-4004 is driven by a V-belt from a pulley on the engine's crankshaft. This design is common on many classic Continental engines. As a new-manufacture unit from a leading OEM of engine components, the Hartzell ES-4004 offers a significant upgrade in reliability and performance over aging, overhauled legacy alternators, ensuring a stable and dependable supply of electrical power.

Key Features

• Genuine Hartzell Engine Technologies Part: Manufactured and tested by a leading OEM of engine accessories, ensuring the highest standards of quality and reliability.

• FAA-PMA Certified: A fully certified, airworthy replacement part, providing a direct-fit, form, and function equivalent for specified original equipment alternators.

• 28-Volt, 38-Amp Continuous Output: Provides ample, stable electrical power for the typical flight and avionics loads of light general aviation aircraft.

• Belt-Driven Design: Features an integrated V-belt pulley and robust mounting lugs for installation on engines configured for a belt-driven alternator.

• Direct Replacement for Ford/Prestolite Models: Engineered as a modern, reliable replacement for the original alternators installed on many Continental O-200 and O-300 engines.

• Efficient Cooling: Incorporates an external fan and an open-frame design for effective air cooling, ensuring reliable performance and a long service life.

Technical Specifications

• Part Number: ES-4004

• Component Type: Engine-Driven Alternator

• OEM Manufacturer: Hartzell Engine Technologies

• Voltage Rating: 28 VDC (Nominal)

• Maximum Continuous Amperage: 38 Amps

• Drive Type: Belt-Driven (V-Belt Pulley)

• Engine Application (Typical): Continental O-200, O-300, and specific IO-360 series engines.

• Governing Specification: FAA-PMA Documentation; Hartzell Engine Technologies engineering drawings.

Aircraft Compatibility

This alternator is a specified replacement part for a wide range of popular general aviation aircraft powered by compatible Continental engines.

• Primary Aircraft Platforms:

  • Cessna 150 (models with O-200)

  • Cessna 172 (early models with O-300)

  • Beechcraft Musketeer series

  • Other aircraft utilizing compatible Continental engine models.

Note: Verification of applicability is the absolute responsibility of the installer. The Hartzell Engine Technologies application guide and the aircraft's Illustrated Parts Catalog (IPC) are the final authorities for confirming part number eligibility.

Applications

• Sole Application: To serve as the primary source of 28VDC electrical power for the aircraft's avionics, lighting, and other electrical systems, and for charging the aircraft's battery.

Why Choose ES-4004?

The aircraft's electrical system is a safety-of-flight system. The ES-4004 offers the opportunity to replace an aging, potentially unreliable original alternator with a brand-new, factory-tested unit from a trusted OEM. This significantly reduces the risk of an in-flight alternator failure, which would necessitate an immediate reliance on the time-limited battery and could create an emergency situation, especially at night or in IMC. For owners of legacy aircraft, this alternator represents a powerful and cost-effective upgrade to the reliability of a critical system.

The long-term reliability of a belt-driven alternator like the ES-4004 is highly dependent on its mechanical construction, particularly its bearings and cooling system. The rotor assembly is supported by two high-quality, permanently sealed ball bearings, which are designed to withstand both the high rotational speeds and the radial loads imparted by the tensioned drive belt. Proper belt tension is a critical parameter; insufficient tension leads to belt slippage and a loss of power output, while excessive tension will dramatically accelerate bearing wear and lead to premature failure. The alternator's thermal management is handled by an external fan coupled with an open-frame design. The fan, driven by the pulley, draws a high volume of air through the alternator's housing, flowing directly over the stator windings and the rectifier diodes—the primary heat-producing components. This continuous forced-air cooling is essential for maintaining component temperatures within their operational limits, preventing insulation breakdown and ensuring a long service life.

Note: This is a flight-critical component. Installation must be performed by a certified A&P mechanic in strict accordance with the engine maintenance manual. The drive belt must be correctly tensioned using a tension gauge. Overtightening will lead to premature bearing failure. This alternator requires a compatible, external voltage regulator (not included) for proper function. After installation, a full electrical system functional check must be performed.

Documentation

Installation and application data are available from Hartzell Engine Technologies. All installation and maintenance procedures must be performed in accordance with the official Continental engine overhaul and maintenance manuals.