I have a 1988 bayliner with a 350 engine and a king cobra outdrive. Reverse would grind a little before going into gear last year(not too much). Now I have no reverse. forward works fine and when placed into reverse it acts like it's in neutral. Drained all the gear oil and found no shavings. One cable drives the shifting. Could this be an adjustment problem at the shifter? Any idea where I should start? Have shop manual which came with the boat.