Replacement parts for a juicer or juice extractor are available from the manufacturer or aftermarket sources. To disassemble and fix these Juice machine.
Disassemble, as above, to access the gear assembly.
Remove the gears and spindle.
Clean and inspect the gears , checking for worn teeth or other components.
Replace parts as needed, referring to the owner’s manual.
Fruit Juice... https://www.apsindustries.in/product/fruit-juice-machine-repair-and-service/