1 Grill turkey, on covered grill, over medium coals 11 to 14 minutes per pound, adding 4 to 9 briquets to both sides of the fire each hour to maintain medium coals.  Brush turkey with melted butter or basting sauce during last 30 minutes of grilling. Continue to grill, covered, 20 minutes. Brush again with butter and continue to grill, covered, about 10 minutes or until thermometer registers 185 degrees Fahrenheit.