when I rebuilt mine I also used RTV to add an additional layer of sealing protection. The starter is at a bad location for getting water in it. I also took the starter apart and sealed around the connections and the case. This is probably the #1 cause of failure with this starter. I hope you also used locktite on all the bolts. There is a lot of torque being placed on those bolts and things need to stay tight to keep water out.