1985 735i engine woes

Hi all - about 3 weeks ago I had a cracked head and had it replaced. After driving home from work last night and getting out of the car I noticed a boiling noise. (Temperature in the car was fine). There were a few drips coming out under the radiator.

I checked the coolant reservoir and it was milky gray - my worst night mare after the $1500 spent only a few weeks prior. The oil in the engine is normal color - although it did alert me to low engine oil a few days ago so I topped it up. I noticed also there was some coolant spray around the top of the radiator.

Please someone tell me that the engine isn't screwed again.. any ideas would be greatly appreciated (and yes - driving it off a pier has crossed my mind),

kindest regards Peter Haworth

Just attempted to flush radiator by loosening the bottom house - the water/coolant in there is perfect - engine oil as said before also perfect. So I'm guessing oil leak from around the water pump. The two hoses up the top have that miolky oil paste inside as well as the reservoir...