Car will not hold water after 4 miles, on 1991 Mercedes-Benz 300SL

Leaking water in the near the middle of the motor or between the fire wall the water runs out of the plastic holding tank after 50 miles and now the motoer get hot after diving about 4 miles, I have no water in my oil, the car runs well, it did get very hold about a month ago

Asked by for the 1991 Mercedes-Benz 300SL
Could be a freeze plug, I was leaking from what looked like the back of the engine only to find the freeze plug on the passenger side of the engine needed replacing