Motorad 623-189 Engine Coolant Thermostat Housing Assembly

Integrated Thermostat Housing for Mercedes-Benz Cooling

Motorad 623-189 is an integrated engine coolant thermostat housing assembly built for Mercedes-Benz cooling systems that require a 189°F opening temperature. It combines the thermostat, housing, and seal in one OE-style service part for direct replacement on select Sprinter, E-Class, R-Class, GL-Class, and M-Class applications.

The Integrated Housing Thermostat line focuses on OE-spec fit and temperature control, using OEM-quality materials and manufacturing processes to support consistent coolant regulation in demanding driving conditions.

Key Features

• 189°F start-to-open temperature for OE-specified cooling control
• Integrated thermostat housing assembly with thermostat and seal
• Bleeder hole and jiggle pin included for air management during service
• Aluminum, stainless steel, and copper construction
• Rubber gasket/seal included
• 4 bolt holes and 1 outlet port
• Silver finish with 1.91 in outlet diameter
• OE supplier manufacturing with OEM specifications and processes

Detailed Description

Motorad 623-189 is an engine coolant thermostat housing assembly engineered for Mercedes-Benz vehicles that call for a 189°F thermostat. The copper case and wax compound are used to respond quickly to coolant temperature changes, helping the engine reach and maintain the proper operating range. The offset design, air relief valve, bleeder hole, and OEM-style seal support a service-ready replacement for cooling system maintenance.

This part cross-references Bosch 62389 and Dayco 86105 for the same application. It is a direct-fit option for Mercedes-Benz Sprinter 2500, Sprinter 3500, and Sprinter 3500XD models, as well as select E350, R350, R320, GL320, and ML320 applications. Motorad 623-189 is built for buyers searching for a Mercedes-Benz Sprinter thermostat housing assembly, a 189 degree coolant thermostat, or an OE-style integrated thermostat housing replacement.

What It Helps Address

• Coolant temperature that stays too low or takes too long to stabilize
• Thermostat housing leaks at the seal or mating surface
• Air trapped in the cooling system after thermostat service
• Temperature control issues caused by a worn thermostat element
• Replacement needs on Mercedes-Benz Sprinter 2500, Sprinter 3500, and Sprinter 3500XD cooling systems

Installation Notes and Tips

Verify the OE-specified 189°F temperature before installation and confirm the housing orientation matches the engine layout. Inspect the mating surfaces, replace any damaged coolant hoses or clamps, and bleed the cooling system carefully using the integrated bleeder hole and jiggle pin. This part is listed for Mercedes-Benz Sprinter 2500, Sprinter 3500, and Sprinter 3500XD applications, along with select E350, R350, R320, GL320, and ML320 models.

Quality Assurance

Manufactured by an OE supplier using OEM-quality materials, this thermostat housing assembly is produced to OEM specifications and processes for consistent fit and temperature response. The design uses OEM-style seals where applicable and is built to meet the demands of modern automotive cooling systems.