Mercedes W910 OM651 Fuel Return Line Overflow Pipe Hose A6510700600

The Mercedes W910 OM651 Fuel Return Overflow Hose is a component from the Lines, Hoses, and Tubes group, designed for diesel engine fuel supply systems. Engineered for the OM651 unit in W910 series models, it ensures stable fuel return in the common rail system, contributing to smooth diesel engine operation.

Specifications and technical data

• SKU: A6510700600
• Mark: Mercedes (Genuine OE)
• Condition: Used
• OEM Part Number: A6510700600
• Substitutable numbers: A6510700600, A 651 070 06 00
• Fuel type: Diesel
• Category: Hoses, Lines & Pipes

Purpose and Function in the Fuel System

The fuel return overflow hose is responsible for draining excess diesel fuel from the fuel rail or injectors back to the tank, stabilizing pressure within the supply system. In the OM651 diesel engine, this is crucial for:

• maintaining proper operating pressure in the common rail system,
• limiting fuel overheating in the circuit,
• ensuring uniform injector operation under varying loads.

With a correctly selected return line, the fuel system operates stably, and the risk of fuel metering disturbances is reduced.

Construction and Fit for the OM651 Engine

This component belongs to the Lines, Hoses, and Tubes group, meaning it is structurally adapted to operate in a diesel fuel environment and for installation in the engine bay. The shape and connector diameters are tailored to the OM651 unit's architecture, facilitating proper hose routing and connection to existing fittings.

Correct routing of the return hose minimizes the risk of abrasion, leaks, and improper positioning near heat-generating components, which is important for the long-term, safe operation of the fuel system.

Benefits of Using an Original Hose

Using an overflow hose specifically designed for the OM651 diesel engine allows for the preservation of the fuel supply system's original operating characteristics. Key benefits include:

• precise geometric fit to the engine unit and accessories,
• maintenance of fuel flow parameters in line with manufacturer specifications,
• reduction of leak risks associated with using universal replacements,
• compatibility with other fuel system components in Mercedes vehicles with the OM651 engine.

This solution is particularly recommended when diagnosing issues with starting, rough idling, or fuel metering disturbances, where the condition of the return lines directly impacts repair outcomes.

Operational Characteristics and Condition

The offered overflow hose is a used part, allowing for economical repair of the fuel system while maintaining proper fit for the diesel engine. Such components are often chosen for servicing OM651 units where both structural compatibility and cost control are important.

The fuel return overflow hose in a diesel engine operates under conditions of varying pressure and temperature, so its condition is crucial for the overall system's integrity. Replacing a worn or damaged component with a correctly selected hose helps reduce fuel leaks and potential system air ingress.

Expanding Fuel System Service

If you are planning a comprehensive repair or upgrade of the engine area in your Mercedes and require other parts from the same group, such as supply lines, flexible fuel hoses, or rigid return tubes, check the available parts in the Mercedes Lines, Hoses, and Tubes category.

When selecting used parts for a diesel fuel system, it is advisable to consciously compare original, aftermarket, and used solutions – a detailed discussion of cost and quality differences, as well as OEM number compatibility, can be found in the article Original, Aftermarket, or Used – Which Car Parts Offer the Best Value?.