120 hp Johnson starter won't connect with flywheel

[Texhunt]

Hi, I just bought an older model boat with a 120hp Johnson, when I try to start it, the starter just spins, does not connect with the flywheel. What do I need to do?
Thanks, Jim

 

[cyclops222]

Weak battery ? Recharge the battery fully.

 

[McGR]

As stated, make sure the battery is in good shape. Also, be sure all cables and connections are good. Additionally, check the helical splines on the starter drive/bendix. The drive should move freely along the splines. I usually use my secret concoction of WD-40 and graphite to lube the splines. Don't use any heavy lubes.

If none of these work, jump over the power cables on the solenoid with a suitable gauge cable (be careful, as soon as connection is made starter motor will spin...). If this corrects things, the internal contacts of the solenoid are in bad shape and the solenoid needs replacement.

 

[Texhunt]

Thanks for your replies, guys. I am pretty sure that the starter is about 5" x 7" mounted vertically under the flywheel, but I am not sure where the solonoid is and what it looks like. Help, please?
Thanks,
Jim

 

[Texhunt]

OK, I found a solenoid online, so I know what it looks like and can find it on the engine, but can I perform a test to determine if that is exactly what the issue is?
Jim

 

[racerone]

Battery cables hooked up correctly?

 

[Texhunt]

yes sir!

 

[Eddie13]

Texhunt it is most likely a gear reduction starter whereas the bendix on the starter does spin up like normal. The problem is under the flywheel cover. Do you have a flywheel cover with like a 100 bolts ???

 

[Eddie13]

Get your model # and put on here.

 

[racerone]

I doubt the 120 has that gear reduction starter !

 

[Eddie13]

Some do. I think may not . I know some 115 do.

 

[racerone]

I do not believe the 120 models were ever marketed with the 60 degree looper block.--The small 60 degree blocks had the gear down starter.----Load test the battery.----Take starter apart for cleaning , inspection , ohm check on armature.----No beer tokens spent to do this.-----Perhaps new starter brushes if all checks out.