[Superglyde]

Hi all,
I was blowing snow the other night and heard this terrible screech. The blower kept on working, but it sounded like I sucked up metal. In preparing for our next 8 inches of snow tomorrow, I took a look. The yoke (is that the correct term) where the chain is, wobbles around when you grab it, and it looks like the chain ground off the left grease nipple. The shaft I can move from left to right as I turn it and the sprocket rubs up against the left side of that yoke. I can't see how to make it all tight. Is it simply a matter of tightening up the chain with those two tightener bolts to push back and the pressure keeps it aligned correctly?