Four Seasons 85991 Engine Coolant Thermostat Housing

Overview of Four Seasons Thermostat Housing 85991

The Four Seasons Thermostat Housing 85991 is designed for precise engine coolant regulation in select BMW models. This integrated thermostat housing includes the thermostat and is constructed from durable plastic to ensure reliable performance in your vehicle's cooling system.

• Material: High-quality plastic construction
• Includes integrated thermostat for streamlined installation
• Bolt hole center-to-center distance: 1.565 inches
• Inlet port diameter: 1.536 inches
• Flange thickness: 0.408 inches
• Overall height: 5.5 inches
• Compatible with multiple BMW models including 228i, 320i, 328i, 428i, 528i, X1, X3, X5, and Z4
• Meets or exceeds OEM specifications
• Gasket or seal not included

About the Four Seasons Thermostat Housing Product Line

The Four Seasons Thermostat Housing product line focuses on engine coolant components designed to meet or exceed original equipment manufacturer standards. This line provides integrated thermostat housings that simplify replacement and maintenance by combining the thermostat and housing into a single unit. The 85991 part number is part of this line, offering compatibility with a range of BMW vehicles and engineered for precise fit and function.

Detailed Product Description

The Four Seasons Thermostat Housing 85991 is an integrated thermostat housing made from durable plastic, engineered to maintain optimal engine temperature by regulating coolant flow. The housing features a bolt hole center-to-center measurement of 1.565 inches and an inlet port diameter of 1.536 inches, ensuring a precise fit for compatible BMW models. With a flange thickness of 0.408 inches and an overall height of 5.5 inches, this component is designed to match OEM specifications closely. The integrated thermostat included with this housing streamlines installation and reduces the need for additional parts, although a gasket or seal is not included and should be sourced separately.

Common Applications and Issues Addressed

• Replacement for faulty or leaking thermostat housings in BMW 228i, 320i, 328i, 428i, 528i, X1, X3, X5, and Z4 models
• Resolves engine overheating caused by thermostat failure
• Prevents coolant leaks due to cracked or damaged housing
• Restores proper coolant flow and engine temperature regulation
• Addresses issues related to thermostat sticking or malfunctioning

Installation Notes and Tips

• Ensure the engine is cool before beginning installation to avoid burns
• Remove the old thermostat housing carefully to prevent damage to surrounding components
• Use a new gasket or seal as this part does not include one
• Torque bolts to manufacturer specifications to avoid leaks or damage
• Check coolant levels and refill as necessary after installation

Quality Assurance and Warranty

The Four Seasons Thermostat Housing 85991 meets or exceeds OEM standards for fit, form, and function. Manufactured with quality materials and precision engineering, this part is designed to provide reliable service in your BMW vehicle. While specific warranty details are not provided, Four Seasons products typically come with a limited warranty against defects in material and workmanship. Consult product documentation or the manufacturer for exact warranty terms.