I have a 15 year old Snapper that has been used pretty hard, but runs powerfully. The only problem is that when I want it to throw snow it only does so for about 8-20 feet then gets clogged. THis constantly happens. I initially thought is was because the snow was so "heavy/wet". Is this old age, or is there something wrong with it. It's a Snapper 826

If this model has a disc that transfers power from engine to thrower, try adding tension to the cable on the handle that engages the thrower. There is usually an adjustment nut to add tension or slack like a bike cable. It sounds like not enough friction on disc.