Dismounting tool for water jacket of large diesel engine

The embodiment of the utility model provides a disassembling tool for a water jacket of a large diesel engine. The disassembling tool comprises a rack, a gear, a control handle, a limiting block, a supporting plate, a shell and an arc-shaped plate. The first supporting plate is fixedly connected with the rack, and the second supporting plate is fixedly connected with the shell. Through holes are formed in the supporting plates; through holes are formed in the two side faces of the shell, an opening is formed in the top wall of the shell, and grooves are further formed in the side faces of the shell. A hole is formed in the shell, the rack is arranged in the hole, the gear is arranged in the shell, the limiting block is arranged in the shell, the control handle is movably arranged in a groove in the shell, the arc-shaped plate is arranged on the control handle, and teeth matched with the gear are arranged on the arc-shaped plate. When the tool is used, the first supporting plate is supported on the rocker arm