I have just purchased a used 115 Johnson and when operating it it has what I am going to call a clicking sound that appears to come from the upper unit. I had previously owned a 1984 115 Evenrude and it never made this noise and was wondering if any one had an idea of what to look at or is it posible that it is just that much more noisey? It has plenty of power and when I accelerate it seems to go away. It idles fine runs good, starts good and other wise seems very good.Thanks in advance for you help. Regards, Lubertus