Hi, folks. I would like to change the radiator fluid on my 2007 E83 X3. I'm not finding a drain valve on the radiator. Is it necessary to remove a radiator hose to drain the coolant? Also, any special bleeding procedure to get the air out of the system when refilling? Thanks, Doug
Some E83's have a drain on the radiator, and some do not. For the one's that do not have the drain, you have to remove the lower radiator hose. Bleeding, you have to open the bleed screw on top, and fill the system till the coolant comes out. Then close the bleed screw, top and run up to temp. Let cool, and recheck the level.
That's only part of the story. The ignition should be ON (but do not start engine), HVAC temperature on maximum, fan on maximum. This ensures the valves to the heater core are open, allowing any air trapped there to escape. As noted, it's important to recheck the coolant level after a warmup/cooldown cycle and if necessary, top up using the same procedure.
