I purchased Johnson 8 hp made in belgium '86 that acording to previous owner was used once in salt Florida waters. He claims that he flushed it with fresh water after use, is that enough or is there anything else I could do to it, considering that was years ago ? Motor has great even ( on both cilinders) commpresion and starts easily. Anyone has some advice how to treat it (now or in similar situation in future) plase respond...thanks much and regards