Expansion Tank

[gregg3gs]

Few more thing to add:

- mix the coolant with distilled water (50/50 in most cases)
- after you replace the tank, make sure you air out the cooling system (turn the car on, do not start the engine, turn hvac on, set temp to the highest you ca, turn the fan to the lowest fan speed you can, leave on for 15 minutes, listen for pump running: front of the car driver side)

[bdcanetti]

Originally Posted by gregg3gs

Few more thing to add:

- mix the coolant with distilled water (50/50 in most cases)
- after you replace the tank, make sure you air out the cooling system (turn the car on, do not start the engine, turn hvac on, set temp to the highest you ca, turn the fan to the lowest fan speed you can, leave on for 15 minutes, listen for pump running: front of the car driver side)

Keep in mind that is not true for the 4.8i. That was the case on my 4.4i and I believe it may be for the 3.0 but on the 4.8i there is no such bleed procedure. You just fill, leave cap off run at idle for a few minutes, refill if necessary and you're done. WSMEYER explains above as well.

[gregg3gs]

Originally Posted by bdcanetti

Keep in mind that is not true for the 4.8i. That was the case on my 4.4i and I believe it may be for the 3.0 but on the 4.8i there is no such bleed procedure. You just fill, leave cap off run at idle for a few minutes, refill if necessary and you're done. WSMEYER explains above as well.

what!!!!?????

Sorry for misinformation. Hope you are not offended, I will double check.

[bdcanetti]

Originally Posted by gregg3gs

what!!!!?????

Sorry for misinformation. Hope you are not offended, I will double check.

I'm not offended at all! It's just a crappy lesson all us 4.8i owners had to figure out. Any other BMW I've had you had to do the procedure as you explained. It took a bunch of reading and talking to my service department to learn there is no bleed procedure on the 4.8i.