I have a 1980 Hunter 27 with a Renault RC8D diesel. I have been searching for the correct impeller for my water pump for most of the winter. I have tried all of the parts distributors for Renault. My problem has been that the existing impeller does not have any identification numbers on it. Consequently they keep sending me the wrong size and style impeller. It turns out that my Renault Engine was actually built in May 1979. Do any of you Hunter 27 owners with a 1979 manufactured Renault have any impeller information or I.D.#. My impeller has 6 blades and has a through hole pin drive type shaft. Last summer I had to rig a temporary cooling system with an electric pump. However it is a hastle and also a drain on the batteries. If I can't find the correct impeller I may try to replace the pump with one that has a standard size impeller. If anyone can supply any information it will be appreciated.