451-787 - Piper Aircraft OEM Brake Bleeder Cap

451-787 – Piper Aircraft OEM Brake Bleeder Cap

Available now on the Airparts.aero Marketplace.

Overview

The Piper Aircraft 451-787 is a genuine Original Equipment Manufacturer (OEM) brake bleeder cap, an essential component for the hydraulic brake systems on a vast range of Piper aircraft. This cap is designed to thread onto the brake bleeder screw, typically located on the brake master cylinders or calipers. Its primary functions are to provide a clean, sealed interface for brake bleeding equipment and to protect the sensitive bleeder valve from contamination by dirt, moisture, and debris. As a genuine Piper factory part, it guarantees the precise fit and material compatibility required for maintaining your aircraft's braking system to factory standards.

Key Features

• Contaminant Protection: Creates a positive seal over the bleeder screw orifice. This is critical for preventing dirt and moisture from entering the valve, which could otherwise contaminate the hydraulic fluid or cause corrosion.
• Clean Bleeding Interface: Provides a uniform, clean point of connection for the hoses from pressure or vacuum brake bleeding systems, helping to make the maintenance process efficient, safe, and spill-free.
• Durable Plastic Construction: Manufactured from a durable plastic polymer selected by Piper for its resistance to MIL-H-5606 hydraulic fluid and its ability to withstand the cockpit and wheel well environments.
• OEM Specification: As the genuine OEM part, it is manufactured to the exact dimensional specifications required by Piper for their certified aircraft, ensuring a perfect, secure fit on the bleeder valve.
• Direct Fit Replacement: Engineered as a direct, drop-in replacement for a missing or damaged original cap, restoring the protective function of the brake system's service points.

Technical Specifications

• Part Number: 451-787
• Manufacturer: Piper Aircraft, Inc.
• Component Type: Brake Bleeder Valve Cap
• Material: Plastic Polymer
• Primary Application: Piper Aircraft hydraulic brake systems (Master Cylinders & Calipers)
• Certification: FAA Production Approval

Aircraft Compatibility

The Piper 451-787 is the standard OEM cap for the brake systems used on a significant portion of the Piper fleet, from trainers to high-performance singles and twins. It is imperative to consult the specific aircraft's Illustrated Parts Catalog (IPC) for final verification.

• Common Aircraft Families:
  • PA-28: Cherokee, Warrior, Archer, Arrow
  • PA-32: Cherokee Six, Lance, Saratoga
  • PA-34: Seneca
  • PA-44: Seminole
  • PA-46: Malibu, Mirage, Matrix
  • And many other Piper models.

Applications

The 451-787 is a small but vital component for the safe and effective maintenance of the aircraft's braking system:

• Brake System Maintenance: A key part that must be removed and reinstalled every time the brake system is bled to remove trapped air.
• System Integrity: Protects the hydraulic system's integrity by keeping the bleeder port, a direct path into the system, clean and free of debris.
• Routine Inspections: Frequently replaced during annual or 100-hour inspections if the original cap is found to be cracked, brittle, or missing.

Why Choose 451-787?

A clean and properly sealed brake bleeder valve is critical for ensuring that air cannot be inadvertently introduced into the hydraulic system and that the system remains free of contaminants. Using the genuine Piper 451-787 OEM part ensures you are installing the exact component that the aircraft was certified with. This guarantees a perfect fit on the bleeder screw and proper material compatibility with the hydraulic fluid, providing peace of mind that this critical service point is protected as the manufacturer intended.

Order Your 451-787 Brake Bleeder Caps Now

Maintain your Piper aircraft to factory standards with genuine OEM components. Visit Airparts.aero to order your 451-787 brake bleeder caps today.

The aircraft brake system is a closed hydraulic loop where fluid pressure is used to actuate the brake calipers. The only intended exit point for fluid or air is through the orifice in the bleeder screw. The 451-787 cap acts as the first line of defense for this critical port. By keeping the external threads and the valve seat clean, it ensures that when the bleeder screw is loosened during maintenance, no dirt or grit is inadvertently drawn into the hydraulic fluid, which could otherwise score the sensitive seals within the master cylinder or brake caliper pistons, leading to leaks and reduced braking effectiveness.

Note: This component should be installed hand-tight. Do not overtighten. It is designed to be a protective dust cap, not to hold hydraulic pressure. The bleeder screw itself provides the primary seal for the hydraulic system.