BMW m47 engine has 2 thermostats. One is main thermostat other is egr thermostat. Egr thermostat is easy to replace, main thermostat is a bit more work.
If your temperature is not aprox 85-90 c in a few km then you have thermostat problem. Another indicator of bad thermostat is blocked dpf, high consumption, louder engine.
You can check your temp in this hidden menu on your instrument cluster.
First you need to do is remove top and bottom engine cover and flush coolant from radiator.
Then remove hose from egr valve and air filter intake and intake hose from turbo. Put some paper in turbo, because you don’t want something to fall in it.
Then remove complete egr cooler, there are quite a lot of bolts.
And now you can remove old thermostat.
There are 2 m6 screws on engine to remove this right hose!
After removing it clean good surface and be carefull, because you don’t want that something falls in it.Some coolant will go out from the engine.
Here is old thermostat it looks like nothing is wrong with it.
And here is new from Gates.
Then install new thermostat, make sure you connected all hoses and tighten all screws. Open this valve to remove air from coolant. You can use old coolant, just use cloth to remove all dirty things from it.
Here is my temp after 100km before replacement.
And after replacement:
Consumption is much lower,finnaly dpf reg works, engine runs much smoother.