Thermostat

[Leeo]

Hi all,
When I did timing belt kit job on my 325i I changed the thermostat as well. I believe it was 80c. Now when the car is idling the temp goes to middle but on freeway it goes down to the level between the quarter and half. Is the thermostat too cold? Or stuck? Do you recommend leaving it or change it? If so what temp do you recommend? I live in the Midwest and don’t drive the car in winters.

[McGyver]

That's exactly how my temp gauge reads with a new 80F thermostat. I would leave it and not worry.

[ZeKahr]

Mine was reading that way fully warmed up before I changed the thermostat. Now it’s just a hair past the 1/4 mark fully warmed up. Moves up to between 1/4 and 1/2 during standstill.

Anywhere between 1/4 and 3/4 is fine from what I’ve read online. The 325i owner’s manual I found online says that anywhere between the read and blue marks is considered normal operating temperature. The temp gauge is not linear.

I’m wondering why BMW didn’t just make the temp gauge three lights - blue for cold, white for normal operating temp, red (possibly flashing) for overheating engine - if they designed the it to behave that way. Would have been much more intuitive for the driver that way

[digger]

the freeway temp guage readng is the actual 80C because with the high airflow it can regulate (open/close so to speak). it rises at idle because of lack of airflow through radiator and the thermostats is continuosly open and accordingly a lower t-stat wont change that. when stationary its only the clutch fan pulling air that dictates the cooling capability. if the clutch fan is good and the system is bled correctly then you are good to go. the thermostat does not sound like it is stuck closed othwerise it would still get hot on freeway