Need a little help. I have an 860 that I just can't get to run right. Long story short is I let my dad borrow the tractor last year to put gravel in his driveway (it has a bucket). After letting it set a while, he couldn't get it started so he had a friend come take a look at it. After adjusting and cleaning the points, it started but was really rough. I brought it home on the trailer and left it until now. Found out the clip that holds the rotor tight on the distributed was missing. Replaced that, the rotor, and the dust cover. Starts right up, but is popping and running rough. Almost seems out of time. Could it be the points again? Or is there something I should be looking at that I'm missing.