Starter spins but does not engage flywheel

2002 Mercury 50hp OB starter spins but doesn't engage flywheel. Replaced starter no change. Jumped two large connections on solonoid does same thing. Will check connections, any other ideas? Thanks in advanced

Re: Starter spins but does not engage flywheel

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.

Re: Starter spins but does not engage flywheel

Agreed with above also check the bolts holding the starter to the block, make sure they are clean w/no corrosion and tight.

Re: Starter spins but does not engage flywheel

If you are using the butterfly connector bolts on the battery, really crank those babies down with a pair of pliers. Better yet, replace them with regular nuts and washers to assure a great connection.

Re: Starter spins but does not engage flywheel

Is the starter spinning in the right direction? Battery in backwards?

Re: Starter spins but does not engage flywheel

Possible causes: Motor spinning to slow, gear is stuck, motor is spinning backwards. battery voltage to low.

One important question, is the gear on the starter motor rising up when it spins? Does it slide up easily by hand? It should.