Johnson 28hp Jahr unknown doesn't start

[auctionsbay]

Hello.
I have Johnson identified as 28HP (please refer to pictures attached). Manual start. The motor doesn't start. Ignition checked - spark OK but i noticed to much fuel come into as the spark plugs become wetty after turning the magneto.
The engine was running OK. The last time I started it the engine run for 10 sec and stopped.
What coulkd be the problem?

 

[racerone]

Looks to be about a 1990 model.-----Check the flywheel key.

 

[auctionsbay]

Looks to be about a 1990 model.-----Check the flywheel key.

Thank you for that. Where is this key located please.