Lowering water temp.?

[Olgeezer1]

Just wondering if this can be done with a simple thermostat change like in the old days or if now it's ECU/electric water pump controlled and a thermostat change would have basically no effect. I know the 210+F. temps. I see on my Scangauge are "normal" but can't help but think since heat is pretty much the enemy of all things mechanical, that a temp. in the 180-190 F. range would be better in terms of component longevity and perhaps performance as well.

[RoundelM3]

Believe it or not, those engineers at BMW who design the cars and engines really know what they're doing. Changing the thermostat may or may not harm the engine, but remember that these engines are computer-controlled, and if you change the coolant temp via a thermostat change, the computer is going to attempt to compensate for the change. I'd say leave it alone or, if your thermostat needs replacing, get the correct BMW spec unit.

[E90ALLMANUAL]

The thermostat and water pump on the N52 change output depending on engine temp and load. It can be fully close thermostat and off pump, something in the middle or both wide open full speed. Same with the electric fan.

[Dackelone]

For emissions purposes.... you want the engine(and catalytic converter) to get hot, up to temp as fast as possible. This is why the temp gets so high so quickly. The engine oil also performs best when warm than when cold.

[MarkkyyMan]

^Nailed it.

[Olgeezer1]

Originally Posted by Dackelone

For emissions purposes.... you want the engine(and catalytic converter) to get hot, up to temp as fast as possible. This is why the temp gets so high so quickly. The engine oil also performs best when warm than when cold.

Yeah I understand that , but my priorities are different. Long life and performance are what I'm interested in with the emphasis on long life. Seems to me everything would be a lot happier at 190 F than 210+F. Seems like it would take an adjustment in the ECU plus thermostat change and that probably puts it out of reach.

[BrokenVert]

Well BMWs solution to heat problems was to add a secondary radiator in the 135 PPK and the 1M. Something like that is probably your best bet. A larger core aluminum radiator wouldn't hurt, too.

[The Wind Breezes]

First of all, the lubricated engine parts, and the oil are HOTTER than your coolant once the car warms up. The car was DESIGNED to run at the temperatures you're seeing. Furthermore, the coolant temp is a byproduct of the boiling point of water under whatever pressure the cooling system runs at, and you'll see this temperature on every production car made these days, unless the thermostat is broken and it won't warm up. Basically, they keep the water as hot as they can without actually boiling it--the system works most efficiently this way.

Now, you could change your OIL cooler thermostat, but you almost certainly don't need or want to, since the car will run at its best at the temperature it was designed for.

It's really beyond me why someone who CLEARLY has no idea what he's talking about would think they can make the car work better than BMW.

[Fast.asleep]

Originally Posted by The Wind Breezes

... the car will run at its best at the temperature it was designed for.

The design goal was cleaner emissions not longevity.

OP: cars are incredibly more complex than they used to be. Id start by changing the coolant and add a bottle of water wetter. Properly maintained these cars will last a long time just as they are. Save your money for when something breaks.