The thermostat regulates the temperature of your coolant. At a predetermined temperature the thermostat will open to let coolant flow to the radiator and be cooled by airflow or the fan. Over time the thermostat will become stuck open or closed, leading to a variety of issues. A closed thermostat will never allow the coolant to reach the radiator and be cooled. Hot coolant will continue to circulate through the engine and absorb even more heat until boiling and the system overheats. An open thermostat is not as bad but is still not ideal - the coolant is always cool, with the temp needle always reading in the cool range. This tells the ECU to richen the fuel mixture to bring the car up to normal operating temp. So your fuel mileage decreases and the car runs rich.  

Replacing the thermostat is an easy but messy job. This thermostat includes the main o-ring (but a housing gasket may be required). Consider replacing the housing and any associated temp sensors while you're in there. The cooling system will need to be bled after.  

Most of the engines from the mid-1980s through the 1990s use the same thermostat design and they are interchangeable among the different temperatures. This is the 68*C thermostat, at the bottom of the temperature range. It should only be used in racing situations such as when deleting the engine fan. However, keep in mind that BMW spent a lot of time engineering the cooling system to work in all kinds of conditions and changing thermostat temperature is not recommended to fix any failures in the cooling system.  

Mishimoto makes coolant tanks, radiators and much more for your Mini/BMW. Established in 2003 their commitment to absolute quality in the aftermarket world is evident through the quality and performance enhancing products they offer.
 

This thermostat fits the following BMWs:   
1977-1983  E21 BMW  323i  
1986-1991  E30 BMW  318is 318ic 325e 325es 325i 325ic 325is 325ix  
1992-1999  E36 BMW  318i 318is 318ti 318ic 323is 323ic 325i 325is 325ic 328i 328is 328ic M3  
1982-1988  E28 BMW  528e  
1986-1988  E28 BMW  535i  
1989-1995  E34 BMW  525i 535i  
1997-1998  E39 BMW  528i  
1986-1989  E24 BMW  635csi  
1988-1994  E32 BMW  735i 735il  
1997-2000  Z3 BMW  Z3 2.8 M Roadster M Coupe 

Ensure your BMW's engine performs at its peak with the installation of this highly efficient oil cooler from Mishimoto. Even in ideal driving conditions, elevated oil temperatures can lead to decreased pressure and compromised engine lubrication. This comprehensive kit includes four feet of stainless braided line, adapter fittings, and an oil filter sandwich adapter, all meticulously designed to reduce oil temperatures and uphold optimal driving circumstances.

• Rows: 19
• Overall Dimensions: 13" x 5.5" x 2"
• Core Dimensions: 11.25" x 5.5" x 2"
• Braided Hoses: 4ft .75 inch & 4ft 9 inch
• Braided Hose Fittings: -10AN
• Sandwich Plate Fittings: -10AN

Please take into consideration that this product may be subject to Proposition 65 (Safe Drinking Water and Toxic Enforcement Act of 1968). Proposition 65 is a California law that applies to companies selling products in California and necessitates the disclosure of chemicals known to cause cancer, birth defects, or other reproductive harm when present at levels exceeding specified thresholds. For further information regarding California Prop 65 warnings, visit www.P65Warnings.ca.gov.

Universal Oil Cooler Black - 10 Row is engineered to maintain optimal oil temperatures and ensure peak engine performance under various driving conditions. This high-performance oil cooler effectively reduces oil temperatures, preventing a drop in pressure and maintaining proper engine lubrication. Featuring a robust 10-row design, it offers superior cooling efficiency compared to standard coolers.

• Efficient Cooling: The 10-row design enhances cooling capacity to manage high oil temperatures effectively.
• Durable Construction: Black finish provides durability and resistance to environmental factors.
• Optimized Performance: Helps prevent a drop in oil pressure and maintains proper engine lubrication.
• Versatile Fitment: Universal design suitable for various vehicles and applications.
• Compact Size: Overall dimensions of 12.95" x 3.8" x 1.97" and core dimensions of 11" x 2.76" x 1.97" ensure a good fit in most engine bays.

WARNING! Prop 65 may apply to this product. Proposition 65 (Safe Drinking Water and Toxic Enforcement Act of 1968) is a California law that applies to all companies selling products in California. Prop 65 requires any listed chemical present above very low levels that are known to cause cancer, birth defects, or other reproductive harm. For more information about California Prop 65 warning see: www.P65Warnings.ca.gov.

BMW & MINI Universal Oil Cooler - 10 Row is a versatile cooling solution designed to enhance the performance and reliability of BMW and MINI vehicles. This high-quality oil cooler provides efficient cooling for the engine oil, ensuring optimal operating temperatures and extending the life of vital engine components.

Crafted with precision engineering and durable materials, the BMW & MINI Universal Oil Cooler - 10 Row is compatible with a wide range of BMW and MINI models, offering versatility and ease of installation. It effectively dissipates heat from the engine oil, reducing the risk of overheating and engine damage.

• Enhances performance and reliability of BMW and MINI vehicles
• Efficient cooling for engine oil, ensuring optimal operating temperatures
• Extends the life of vital engine components
• Compatible with a wide range of BMW and MINI models
• Versatile and easy to install
• Crafted with precision engineering and durable materials

Investing in the BMW & MINI Universal Oil Cooler - 10 Row is a smart choice for BMW and MINI owners looking to improve their vehicle's performance and longevity.