Failure to start - loose wire

Here is the picture.  I'm thinking oil sensor as there is no toggle switch.  

As your a new member, they won't let you post pic's for awhile.
 
Re the oil LEVEL wire (it's not pressure switch), if the oil level is low, it'll hamper spark.
Disconnecting it will disable it and allow for full spark.   
 
Adjacent to the flywheel, (under the pull starter) is the ignition coil. There's a thin wire
connected to it which is your coil KILL wire. 
Ground it, you loose spark.  if you disconnect it
you should have nothing to kill the spark- coil keeps firing..
 
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