Small electrical fire on my YTO ?

I had another almost disaster last night while moving some dirt luckily I got it shut down and was close enough to a water hygrant I got it put out before the fire got to the fuel line. I cant remember how to post a pic here, I know I did it before though.

At any rate there is what looks to be some kind of a sensor that goes into the front of the flywheel housing behind the injector pump that has a short wire on the end with a plug connector . Somehow it shorted out against the block and caught fire I smelt the wires burning and seen the small flames and was able to get it put out and shutdown before it caused any damage . I unplugged the burnt part of the plug and cut the wires coming out of the sensor and restarted it . Everything seems to work and function correctlly so I cant figure out what it could be or what its use is.  

  I dont have a book that shows the engine and my book that shows the wiring diagram gives very little info of whats what . Does anyone have any idea of what it could be or if I can get a new one? It looks like it would unscrew from the front of the housing and has about a 6 inch pigtail with a plug on it that plugs into a square box about 6 inches away. There is also another plug that looks similiar that goes directly into the top of the side casing but it did not get damaged . I know without pics that not a very good description but its the best I can do at this time . I ran it for about another hour without it being connected so I really dont know if its some type of safety switch or if I even need it . Thanks in advance for any input , Bob