well i'm back.. aq125 in a 1984 bayliner. the marina just put the correct prop back on my boat, a 15x15r. took her for a quik test run and she wont get over 3000 rpms. i ran it at 3000 for about 5 minutes when i started to notice a faint tapping noise coming from the valve cover. is this a valve adjustment? and could that be part of the problem with rpm loss? when i returned to my slip the motor started to run alittle rough.