Industrial Injection 23K401 VP44 Bosch Overflow Valve Install Kit with Sealing Washers

The Industrial Injection 23K401 is a complete overflow valve install kit for the Bosch VP44 fuel injection pump found on 1998.5–2002 5.9L 24-valve Cummins diesel engines. Unlike the standalone overflow valve, this kit includes all required components — the overflow valve and sealing washers — so you have everything needed for a proper, leak-free installation in one package.

The VP44 overflow valve (also called a pressurizing valve or check valve) plays a critical role in maintaining correct fuel supply pressure to the injection pump. A worn or failed overflow valve can cause low fuel supply pressure, hard starting, and rough running — even when the lift pump itself is functioning correctly. Replacing this valve as part of any VP44 service or repair is a recommended best practice.

Kit Includes:

• Bosch VP44 overflow valve (pressurizing/check valve)
• Sealing washers required for installation

Key Features:

• Complete install kit — no additional hardware needed
• Replaces OE part numbers: 3941156, 1467445003, 4089577, 5011824AA
• Sourced and kitted by Industrial Injection, a leading diesel fuel system specialist
• Helps restore proper fuel supply pressure and eliminate fuel pressure-related fault codes
• Recommended sealing washer replacement prevents leaks and repeat repairs

Whether you're performing a full VP44 pump service or diagnosing a fuel pressure issue on your 24-valve Cummins, the Industrial Injection 23K401 overflow valve kit provides a complete, quality solution backed by one of the most trusted names in diesel injection.