Starter gear engages flywheel, but doesn't turn.

[RAM1961]

Hi, I'm actually not new here, but my old ID was associated with an email that no longer exists.

So I have a 2012 Merc 115HP EFI. Never have had any problems with it, including last weekend out on Flathead Lake. Well, we were planning going out yesterday, but I'd hear one click and then nothing. So I went thru all the usual suspects - lanyard kill switch ok, made sure connections at battery were clean and tight, then popped the cover of the motor-checked connections and fuses - all as they should be. Then I noted the start gear engaged with the flywheel. I pulled the starter gear back down and had my wife climb in and try to start it why I watched. Sure enough, start gear engaged, but wouldn't turn flywheel. I'm ready 12.5-12.7 volts at battery and back at the motor as well. Any idea what I'm missing, or do I have a bad starter/solenoid?

 

[gm280]

Okay RAM1961, :welcome: to iboats...again? IDK

When you read the battery voltage, was that while trying to start the engine or just sitting there? If that was the voltage while starting the engine, then you could have either a bad starter solenoid, cable connections, starter, or ground connection. That is IF you can turn the engine over by the flywheel. If the engine is locked up, it won't turn. So rule that out first. Then go to the connections at the starter solenoid and even the starter and ground cable at the engine. You can also jumper the starter solenoid to see if you can get the starter spinning. If you can, you have a bad starter solenoid. If you can't, it could be the starter itself. If you can jumper from the large positive terminal (battery supply terminal) at the starter solenoid to the small terminal of the solenoid and it spins, you either have a bad starter solenoid or your key switch isn't supply the voltage to that same small terminal on the starter solenoid or even a bad ground from the other small terminal to ground on the starter solenoid. Think of the starter solenoid as merely a large relay. Because that is exactly when it is. Of course this is all depended on your battery being fully charged and work properly. If the battery is suspect, all bets are off until that is fixed first. JMHO

 

[RAM1961]

Thank you for responding. As noted earlier, battery has 12.5+ volts without key on. So I ruled that out. I didn't know if it was safe to jump the solenoid - I've done it on passenger vehicles all the time, but never on a boat....will go try that.

 

[gm280]

Thank you for responding. As noted earlier, battery has 12.5+ volts without key on. So I ruled that out. I didn't know if it was safe to jump the solenoid - I've done it on passenger vehicles all the time, but never on a boat....will go try that.

Do a voltage test when you are cranking the engine as well. I'd be interested in seeing if the battery is holding up with a load on it.