Okay so a few weeks ago I changed my water pump and everythign was kosher...now suddenly a month later I have ANOTHER leak, this time I have isolated it to behind the engine block. this is a pretty massive leak(all of the colant leaks out in a matter of minutes), causing massive amounts of steam from under the hood. Could it be the water pump? or somethign else?

 

possible freeze plug

 

If its from the "weep hole", then it'sthe seal on the water pump shaft. If from around the pump, re-seal it. If from anywhere else, it's not from the pump (the leak), but may have been caused by the pump...if you let it overheat. If the new pump is defective and the impeller is slipping, it could cause the engine to overheat.

 

Which engine? Makes a big differnce in the possible culprits.