K & R Marine

I had an impeller replaced in May 2017. Today ( August 22 ,2017) when I took the boat out on the water the engine started to heat up and no water was circulating. After being towed back to the dock, I called K&R, talked to the owner who informed me that there was no warranty on his work. I could get another diagnostic done at a cost. What type of mechanic does work that only lasts for 3 1/2 months? It is unfortunate for this business that I will now spread the work of his poor service and lack of customer satisfaction. A.Gfeller