Engine Coolant Thermostat Housing Assembly Replacement for 11537644811, Compatible with 2014-2021 BMW 230i 320i 330i 330e 420i 430i 520i 530i 530e 630i 740e X3 X4 Item Description Replace Part Number: Housing assembly replacement for 11537644811 Adaptation Model: Compatible with 2016-2019 BMW 120i 125i 740e 740le 740le xDrive, 2019-2020 BMW M135i xDrive F40, 2015-2020 BMW 220i 320i 320i/330i xDrive, 2014-2019 BMW 225i, 2016-2020 BMW 330e 330i 420i 420i, 2017-2020 BMW 230i 430i 420i/430i xDrive 520i 530i 530e 630i, 2015-2019 BMW X1 sDrive xDrive, 2018-2020 BMW X2, 2017-2019 BMW X3, 2018-2020 BMW X4 Z4 Replacement Thermostat Kit: The thermostat works by regulating the flow of coolant through the radiator to keep the engine at its stable operating temperature and prevent overheating Make of Quality Plastic: High temperature resistance, wear resistance, corrosion resistance. After professional testing, meets OEM standards Easy to Install: Direct replacement of old parts, simple to operate, save time and peace of mind. Please read description and compatibility chart before purchase ? See more product details Structure: includes Housing, thermostat, rubber gasket Function: Regulates the flow of coolant through the radiator to keep the engine at its stable operating temperature and prevent overheating 1. The thermostat main valve opens too late or too early, if it opens too late, it will cause the engine to overheat. 2. If it opens too early, it will prolong the engine warm-up time and the engine temperature will be too low, thus affecting the efficiency. 3.Simply put, from the water temperature gauge to see the engine water temperature is too high or too low, you may need to replace the thermostat! The following methods to determine the thermostat failure 1, After the engine startup check, open the cooling water tank filling cover, look at the cooling water tank cooling water whether by the temperature of the upper and lower water pipe can determine whether there is water flow phenomenon, if not that shows that the thermostat is damaged or there is a foreign body stuck in the main valve switch 2, You can feel the temperature of the upper and lower water pipes by hand can be judged, first of all, the engine will start, 3 minutes after the upper and lower water pipes, if it is a good thermostat, the temperature of the upper and lower water pipes and water pipes are not the same as the temperature of the upper water pipe is generally hot and the lower water pipe is cool. If the thermostat is good, the temperature of the upper and lower water pipes is different, and the upper water pipe is hot and the lower water pipe is cool (1) Thermostat does not open, the water temperature gauge shows high temperature area, the engine temperature is high, but the coolant temperature in the tank is not high, touch the radiator does not feel hot 2) If the thermostat is not closed, the water temperature will rise slowly, especially in winter, and the idle speed will be high. Payment We accept payment only through PAYPAL Shipping We ship products worldwide through standard express courier service, it will reach within 7 to 10 days to abroad buyers, we ship the product after recieved clear payment and give full information about shipment to the buyer Return We accept product return 25 days from delivery date but product should be in original condition.