Mercedes S 420, 1995. Overheating and oil dropping at the same time.

What is your question?

First problem the engine would not turn over. Repaired and then started overheating and oil gauge dropping. Spark plugs checked. Valve cover gasketS replaced. Drove ok for 500 miles then car overheated again and found top radiator hose off(not sure if I might have left clamp unscrewed). Then I flushed radiator and refilled with fresh coolant. It is still overheating after short drives

What makes this problem better or worse?

Idling makes it worse

How long has your 1995 Mercedes-Benz S420 had this problem?

One week