Maybe you should have put the pins in block before the head gasket... then... Im pretty sure it wouldnt move then... flushing the coolant system has nothing to do with it... 30k ago rebuilt the motor... Im sure the coolant was drained then... the thermostat is what heats the motor up so yeah... with it out it takes a long time... my suggestion... go to Honda and buy the $2 pin and a NEW head gasket...