I have looked in the user’s manual and the parts manual as well as the Universal Toressen Marine web site and I cannot find any mention of a Sacrificial Anode. I assumed that all seawater cooled engines had them but perhaps I was wrong. I'm talking about the pencil type that screws into the engine. Does anyone know if this engine has one and where it might be located? Is there a way to add one or would the shaft zinc be sufficient