The purpose of this project was to design a closed loop cooling system for Buhler Versatile’s new water break dynamometer. The following report outlines the steps taken to develop a closed loop cooling system that will dissipate enough heat from the test dynamometer, which will allow the dynamometer to operate at maximum loading conditions. In addition, the report outlines steps taken to ensure the design meets or exceed all of the outlined specifications supplied by Buhler Versatile. This report also provides details of various components required for a closed loop cooling system, as well as all the supporting calculations and production drawings required for implementation of the design. The primary areas covered in this report include: coolant selection, pumping requirements and selection, radiator design and control system analysis. Each section outlines various alternatives and offers calculations and other supporting details for proof of concept. The results of the analysis show that a six radiator cooling tower utilizing a 50/50 glycol water mixture should be employed to meet the necessary cooling requirements of the new dynamometer. A total cost was not found since some of the material costs are unknown along with some of the costs associated with the gearboxes and drive shafts. Due to time constraints a full payback period analysis was not performed.