head gasket leak .

that was the reason why my head gasket was leaking, because the damn nuts were not torqued down right
 
It is important after "breaking in" a new motor to re-torque the head bolts. Otherwise your just wasting your money and time rebuilding the motor to have to redo it all over again as a head gasket leak can cause a loss in compression thus leading to the eventual breakdown of your topend.