not really sure what's going on

[nizmainiac]

here's my problem, going to hospital for chemotherapy blood tests the other week , i overtake 2 cars the engine decides to drop a valve head , mash a valve seat and throw it out on the inlet side , and the valve head is stuck between the piston and cylinder wall ( so that engine is scrap)

So i source another engine, pull the old one out , do a straight swap (all bits and sensors included ) put the other one in , run it without coil lead on to get oil pressure and it starts up fine, now i know that the cooling system can be a bitch to bleed but i've done that o.k., everything is wired up o.k. too but my speedo isn't working and i'm getting alot of steam from the exhaust.

would the steam be due to the old engine lunching itself and sending most of the coolant out through the head because i noticed that the radiator was less than half full when i stripped it, so could the exhaust hold a certain amount of water and emit steam until it's boiled off ( i noticed that there was antifreeze droplets in the tailpipe just after it happened)
i also have a strange vibration that i can feel throughout the whole car and everything went back in as it came out
iv'e checked the other engine out before i fitted it and all appears to be o.k. why the speedo isn't working i don't have a clue . thanks in advance