^Your water pump has failed. That's why it is loose. That's also where your coolant is coming from. It's coming from the snout of the water pump.

I'm hoping you didn't cook the engine... m54's do not like being over heated. Nor does any other BMW engine actually. My sister in law just cooked her m54's head gasket (01 330i) after loaning her car out to a brother in law. Bad move.

BTW, I also subscribe to the cooling system over haul anytime a car is over heated. Or around 120,000 miles as posted above. I prefer to be able to get in my car and drive it cross country whenever I have to... not worry about a radiator hose, heater control valve hose, water pump, etc. failing on me while I am 1000 miles from home.

Have had 13 or 14 BMW's (4 currently) and love these things. Most recent purchase is our 2005 4.4i X5 Sport.

WP is gone as I mentioned above.

You need to do a cooling overhaul, anything less than that is asking for trouble.

:iagree: I share your concern about engine damage. I would now agree the system should be overhauled since the water pump is gone. The pump is one of the more expensive parts in the system. It should be protected by doing the rest of the system. Plus, you will have much of the system accessible or already disconnected.

My thermostat was replaced when it turned out to be an expansion tank leak, then a few months later, it became a water pump, then it was time to replace hoses, then it was the belts, then it was the pulleys. Save yourself the downtime, and replace parts as a group and you can save yourself the headache. Hoses, belts, and pulleys should be changed together. Water pump and thermostat should be changed together.