N63TU Lower thermostat/Oil Cooler swap

[f10_M550i]

I changed out the Oil Cooler valve for one that was modified to stay open all the time thus running oil through the oil cooler from startup, and changed the thermostat to one that was calibrated at a lower coolant temp of 95C instead of 105C.

Engine temps

Before
225-230F/City
220-225F/Highway.

After
205-210F/City
195-200F/Highway,
so a good 20F cooler, maybe more.

If I start the car cold, and get on the highway the engine temp stays around the 195-198F mark until I get off the highway.


Notes:
The thermostat can be removed without completely removing the Intercooler Expansion Tank, by disconnecting one side of the expansion tank and using a bungee cord to hold it out of the way, and you don't have the remove the water pump (procedure calls for removing the water pump). A ratcheting wrench will get the two front thermostat bolts, and a long swivel extension can get to the back bolt. The bolt heads are male torx. To get to it easy you have to remove the electric fan.

Make sure you follow the correct fill and bleed procedure when refilling the coolant