A hydraulic motor having a cooling system includes a stator, a rotor that rotates and orbits in the stator, a drive link connected to the rotor, and a housing connected with the stator. The housing includes a working fluid inlet port, a working fluid outlet port, a cooling fluid inlet port, and a cooling fluid outlet port. Each port extends through the housing and is configured to connect with a different associated external fluid line. Pressurized fluid enters the working fluid inlet port to rotate and orbit the rotor en route to the working fluid outlet port. The cooling fluid ports are isolated from the working fluid inlet port and the working fluid outlet port within the housing.