Berkley makes rods, reels and combos for fishing. The Fusion is a combo of rod and reel and is retired from the company line. Doing repairs on this style of reel is typically for one of three reasons: tangles, broken or bent cast-bail or dried fixtures requiring lubrication. For other repairs, it is helpful to have a schematic of the reel, available through Berkley directly. Many small repairs are doable without the schematics or manual.
Reel in all line to the Fusion spool. Push the cast-bail wire up to have access to the spool and bushings. Add a small dollop of dry graphite lube onto the spool bushings found on each side.
Remove the handle from the reel, using a small screwdriver. Inspect the bushings for debris or grit. If present, remove using a toothpick or thin knife. Squirt a dollop of dry graphite lube into the bushings.
Inspect the wire cast-bail for bends. If bent, remove and replace with a new one. To remove, pinch the metal edges on the reel sides and pull up and off. Add a new one by pinching it and placing the ends into the housings.
Inspect the entire spool with the line for tangles knots or random strands of fishing line sticking up. If there are more than 10 or 12 tangles, consider cutting off the entire spool of line and rethreading with new line.
Tie new line into the lever-lift on the side of the spool. Thread two coils of line through the lever-lift and pull them down. Thread the end of the line back through the coils and pull tight. This locks the line onto the spool, allowing new line to be reeled up and onto the spool.