Wacker Neuson 5100015052 Fitting Reducing Bush 1/4 To 1/8 NPT ST

The Wacker Neuson Fitting Reducing Bush 1/4 To 1/8 NPT ST is a genuine OEM component designed for the HIF 690 Flameless Air Heater. As a direct OEM part, is manufactured to the exact thread specifications and dimensional tolerances required by the original assembly — no guesswork, no adaptation. Whether you're completing a repair or restoring full airflow function to the heater, this fitting ensures a proper, leak-free connection between the 1/4 NPT and 1/8 NPT ports in the system.

Key Features

• Correct Thread Sizing for Fuel or Air Line Integrity — Machined to exact 1/4 to 1/8 NPT thread specifications, ensuring a properly sealed connection with no cross-threading or pressure loss at the joint.
• Genuine OEM Construction — Sourced directly from Wacker Neuson, this fitting matches the original material grade and thread form used at the factory, so the connection performs exactly as the system was designed.
• Direct Replacement for HIF 690 Flameless Air Heaters — Confirmed fitment for the HIF 690 series, so you can install with confidence knowing this is the correct part for the application.
• Maintains Sealed System Performance — A worn, damaged, or incorrect reducing bush can cause pressure leaks that affect heater output and combustion efficiency. Replacing with the correct OEM fitting restores system integrity.
• Fuel System Safety Relevance — Fittings in heater fuel and air circuits must maintain a reliable seal under operating pressure. Using the correct OEM-spec part supports safe, code-compliant heater operation.

A reducing bush fitting is a threaded adapter used to connect two pipes or ports of different sizes — in this case, stepping down from a 1/4 NPT male thread to a 1/8 NPT female thread. In a flameless air heater like the HIF 690, these fittings are used within the fuel or air delivery circuit to ensure consistent pressure and flow between components. If the fitting is damaged, cross-threaded, or the wrong size, the result is a leak or pressure drop that can reduce heater output, cause rough operation, or create a safety concern in the fuel delivery path.

Part Details

Compatibility & Fitment

Verify Before You Order

Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.

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