[vilhrafn]

Hey guys, nice to meet you all

I am replacing the oil filter housing and I need to drain the high temperature coolant, I downloaded ISTA and got the instructions but they appear incorrect for this step The ISTA instructions for draining the low temperature coolant were correct though.

According to ISTA it is on the left hand side of the radiator, I have been going mad believing my eyes are deceiving me but it simply isn't there. The ISTA instructions are the same as this website, relevant pic included

https://bmwrepairguide.com/repair_se...linder-engine/

https://bmwrepairguide.com/wp-conten...RB17-00634.jpg

does anyone know where I should drain this coolant from? Can't see anything that makes sense except for maybe draining from the water pump. Also can I use the same coolant for the low temperature circuit? Assume so, as this fella does

thanks everyone

[jzeiler4]

What is wrong with draining from the lower left of the radiator. That will drain all the high temp coolant and it is the lowest point in the system. Should be a drain valve there.

[vilhrafn]

It's not there. Do you have a F22 B48 and know for sure?

[jzeiler4]

No but push comes to shove the lower hose is a safe bet.

[vilhrafn]

Originally Posted by jzeiler4

No but push comes to shove the lower hose is a safe bet.

What do you mean lower hose? I said there is no hose going into the radiator other than the low temp circuit hose which is on the right hand side, which I have already drained.

The best place I can see to drain from instead is the water pump, I believe this is lower than the oil filter housing which is what I am having to replace. Wanted to get ideas as ISTA instructions appear incorrect for my car. I'll get some photos later

[ciabatta]

Did you figure this out ? I’ve been baffled since March and just drain from the hose on the bottom of the radiator for low temp circuit . Someone informed me that the low temp circuit hose to radiator will drain both but didn’t elaborate how. ISTA documentation insinuates that the circuits aren’t necessarily connected and both have different draining points.