04 Bayliner won't start!!

Question

My 04 Bayliner with a Mercury 135HP four cylinder in-board/out-board engine won't start. When I turn the key it tries to turn over once then I hear a sharp, repeated tapping noise from inside the engine. How do I fix this?

Answer 1

SOunds like the battery is going dead.  Try putting a slow charge on it, or at the very least jumping it, and see if she starts.  Then you'll probably have to relace the battery.

Answer 2

Does this engine have a timing belt on the front of the engine.  If so, it might be a belt problem, but I agree what it might also be a "Bad battery", If it's original to the boat it's at about it's life expectancy for marine batteries.   It would also be helpful to know howlong its been since the engine last ran.  Storage and "Hydrolic lock" can cause this type sound.  So, start with the battery, then the timing belt, then it'd mechanic time.  Good luck!!!