Four Seasons 85961 Engine Coolant Thermostat Housing

Thermostat Housing for BMW and Land Rover

Four Seasons 85961 is an integrated engine coolant thermostat housing built from aluminum for a direct-fit cooling system repair. It includes the thermostat and gasket or seal, and it meets or exceeds OEM requirements for the listed applications.

Key Features

• Aluminum thermostat housing for engine coolant service
• Integrated thermostat housing style with thermostat included
• Gasket or seal included for installation
• 4 mounting holes with 2.54 bolt hole center spacing
• 38.000 outlet port diameter and 1.260 inlet port diameter
• Flange thickness: 0.403 in; overall height: 3.485 in
• Meets or exceeds OEM specifications

Product Details

This Four Seasons thermostat housing, part number 85961, is an integrated thermostat housing assembly for engine coolant components. The aluminum construction supports cooling system durability, while the included thermostat and seal help simplify replacement of a worn or leaking housing. Four Seasons Thermostat Housing 85961 is listed for BMW 540i, BMW 740i, BMW 740iL, BMW X5, BMW Z8, and Land Rover Range Rover applications across the model years shown below.

This part cross-references Gates 33935 and Stant 14612 for the same application.

Common Cooling System Issues It Can Address

• Coolant leaks at the thermostat housing
• Cracked or warped plastic housing replacement with aluminum construction
• Thermostat sticking open or closed
• Improper engine warm-up or unstable operating temperature
• Cooling system service on BMW and Land Rover vehicles with integrated housing design

Fitment

• Fits 2003-2005 Land Rover Range Rover, N/A; thermostat included in Engine Coolant Thermostat/Water Outlet Assembly Kit; Thermostat Housing
• Fits 1999-2003 BMW 540i, N/A; thermostat included in Engine Coolant Thermostat/Water Outlet Assembly Kit; Thermostat Housing
• Fits 2000-2003 BMW X5, N/A; thermostat included in Engine Coolant Thermostat/Water Outlet Assembly Kit; Thermostat Housing
• Fits 2003 BMW Z8, N/A; thermostat included in Engine Coolant Thermostat/Water Outlet Assembly Kit; Thermostat Housing
• Fits 1999-2001 BMW 740i, N/A; thermostat included in Engine Coolant Thermostat/Water Outlet Assembly Kit; Thermostat Housing
• Fits 1999-2001 BMW 740iL, N/A; thermostat included in Engine Coolant Thermostat/Water Outlet Assembly Kit; Thermostat Housing
• Fits 1998 BMW 540i, N/A; w/ Thermostat; From 9/98; Thermostat Housing
• Fits 1998 BMW 740i, N/A; w/ Thermostat; From 9/98; Thermostat Housing
• Fits 1998 BMW 740iL, N/A; w/ Thermostat; From 9/98; Thermostat Housing

Installation Notes

Verify the inlet and outlet port dimensions, mounting hole count, and housing style before installation. Clean the mating surfaces thoroughly, inspect the cooling system for contamination or pressure-related damage, and replace the gasket or seal as part of the repair. Confirm the vehicle’s year and engine configuration against the listed fitment notes for BMW 540i, BMW 740i, BMW 740iL, BMW X5, BMW Z8, and Land Rover Range Rover applications.

Quality Assurance

Four Seasons lists this thermostat housing as meeting or exceeding OEM requirements for the specified applications. The part number 85961 is built as an integrated thermostat housing replacement for cooling system service on BMW and Land Rover vehicles.