A glass filler defines a main body having a lower surface. An inlet and outlet are each defined in the lower surface of the main body. An outlet chamber is defined in the main body and contains an outlet valve, which includes an outlet valve housing defining a castellated edge. The outlet valve includes a cylindrical sleeve that defines an inner surface that is crenellated and configured to receive an implement that can be inserted and used by the operator to rotate the cylindrical sleeve in a manner that controls the amount of liquid exiting the outlet of the glass filler.