Might be a cracked head !!! hard to say until you get the head off as for cost depends where you are in the world really and what is discovered when the head is off, UK at the moment quite cheap as work is hard to come by.
__________________ VELVET BLUE UK INDIVIDUAL , IM THE LAST
UNITED WE STAND DIVIDED WE FALL
I stepped in a plate of Pasta the other day - now I have to worry about my Carbonara footprint!