I've been trying to tighten my chain on my 330 trail boss and i've loosen the 2 bolts and brake clamp as well and put a screwdriver in the hole through the sprocket to the bearing housing. What I dont get is when I move the atv the whole axle (housing and all) turn and the chain doesnt tighten up any. Please help

 

Jack it up and check the axle bearings.If they are good replace the chain

 

The rear axle's mount is kinda like a cam. Loosen the mount and turn the axle mount until desired.

 

If it isn't sufficiently tight at the tightest adjustments you can sometimes take a link out. That will get you by until you can get a new chain.

That's one thing I hate about those chain machines. you're constantly having to mess with the chain tension.