A parts immersion system and method includes a trough through which a conveyor belt carries the parts. A chemical solution is introduced into the trough through an opening in the bottom of the trough, from above the trough, and/or from the sides of the trough. The parts on the conveyor belt in the trough have a tendency to retard liquid movement out of the open ends of the trough thereby allowing the chemical solution to accumulate in the trough resulting in a greater immersion of the parts in the chemical solution. A gate may be provided near one or both ends of the trough to further enhance the accumulation of the chemical solution in the trough. Flights may extend upwardly from the conveyor belt to further enhance liquid retention in the trough between the flights. Flexible seals at the ends of the flights may contact sidewalls of the trough. One or more vibrators may be provided to enhance drainage of the chemical solution from the parts as the parts exit the trough.