Official M30 Cooling System Bleeding Link

[BDK]

This was poached from the 5er Guys/MyE28.com ...
Thought it should be here as well...

There is a sure way to bleed the cooling system on 'big' six engines.
1. After repair is made (before adding coolant) remove bleeder screw and run
a small piece of wire down the hole to dislodge any mineral deposits..
2. Replace the screw, but leave valve 'open'.
3. Open heater control valve and add coolant until it begins to escape from
the bleeder hole.
4. Now close bleeder screw and replace the expansion tank cap and tighten.
5. Remove the small coolant line that runs from the radiator to the
expansion tank AT THE EXPANSION tank and hold it as high as you can.
6. Now attach another hose the expansion tank in place of the one you've
just removed. BLOW (gently!!) through this hose until coolant emerges from
the small elevated radiator hose.
7. Now remove the 'blow' hose and reconnect the small radiator hose to the
expansion tank..
8. Now top off the expansion tank to the full mark.
9. Start and warm up engine and check for leaks!!
That's it. Good luck.
BTW, this procedure is compliments of Jim Rowe at Metric Mechanic

BTW, It is a Sticky there, prolly should be here too...

Link to said Discussion...

http://www.mye28.com/viewtopic.php?t=58368

[Doughnut]

I still don't understand how so many people have trouble bleeding the cooling system... I don't need/bother holding up the tank, blowing through hoses etc. I just crack the screw, fill the systems till coolant escapes out the bleed then lock of the bleed screw... Done.

[LowR3V'in]

Try it. You may be surprised.