Dayco DP421 Engine Water Pump

Engine Water Pump for Mercedes-Benz Diesel Applications

Dayco DP421 is an engine water pump for select Mercedes-Benz diesel models with V-belt driven engines. It is built for direct-fit cooling system service on classic 300-series applications, including Mercedes-Benz 300D, 300SD, 300TD, and 300SEL coverage where listed.

Key Features

• Engine water pump for belt-driven cooling system service
• Compatible with select Mercedes-Benz 300D, 300SD, 300TD, and 300SEL applications
• Fits V-belt driven engines as noted in the fitment data
• Dayco part number DP421 for catalog and service matching
• Supports cooling system repair on vintage Mercedes-Benz diesel platforms

Detailed Description

Dayco DP421 is a replacement engine water pump for Mercedes-Benz diesel vehicles listed in the fitment data. It covers 1968-1969 Mercedes-Benz 300SEL, 1975-1985 Mercedes-Benz 300D, 1978-1985 Mercedes-Benz 300SD, and 1979-1985 Mercedes-Benz 300TD, all noted for V-belt driven engine systems. If you are searching for a Mercedes-Benz 300D water pump, Mercedes-Benz 300SD water pump, or Mercedes-Benz 300TD water pump, DP421 provides the catalog match for those applications.

What It Helps Address

• Coolant circulation problems caused by a worn water pump
• Overheating linked to reduced coolant flow
• Leakage at the pump housing or shaft area
• Noisy operation from a failing cooling system pump
• Cooling system service on older Mercedes-Benz diesel engines

Installation Notes and Tips

Verify engine configuration and belt drive style before ordering. Confirm the vehicle year and model against the listed fitment for Mercedes-Benz 300D, 300SD, 300TD, and 300SEL applications. Inspect the cooling system, belt condition, and related components during service so the replacement pump can be installed into a clean, properly serviced system.

Quality Assurance

Dayco supplies automotive cooling and drive system components for service applications. Part number DP421 is cataloged for the listed Mercedes-Benz fitments and should be matched to the vehicle’s year, model, and V-belt driven engine configuration before installation.