I have a 1987 260 hp mercruiser with a alpha one outdrive.Every time i shift it into reverse it either grinds until it finally gets into reverse or it more often than not just kills the engine.i have adjusted the shift cables on the engine itself and can make it shift into reverse ok but it will then do the same thing in forward as it did in reverse i.e. die out or grind gears badly.someone told me if i did as much adjusting on the shift cable as possible that the clutch dogs were bad?anyone got ideas for me