90 HP Merc Starter problem

My motor wont start at TIMES. I can see the started spin but it won't engage the flywheel. Not sure if I need a new Starter or a new bendix relay. Any help appreciated.

Probably 95% of all starter problems is electrical. Is the battery fully charged? Check all your connections. They must be very clean and tight. Check the lugs very closely for any signs of corrosion. They can corrode inside where you can't see it and cause the problem you are having. If you know how to do a voltage drop test you could check them that way. Another way would be to temporally substitute the cables with jumper cables. If all the cables have been confirmed good, try jumping the starter solenoid. Just because it clicks does NOT mean its good. If you are sure the solenoid is good have your battery load tested, regardless of age. This brings you to the starter itself. Remove it and have it tested by your local auto electric shop. They can rebuild it for you if needed and save you some money. Let us know how you make out.