alot of times any dog that sees something running sets off thier natural predatory instict to chase and kill it. see if you can turn a few more loose on him so he can catch them by sight, then start waiting until the coon is out of sight to turn the dog loose. if he saw where it went he should head straight that way, if he doesnt see it right off, he should start using his nose. make sure you give plenty of love and reward when he smells one right, esp if he rears up and trees it. he might mark or signal the correct tree the first time, but i would bet getting him to tree like a coon dog is going to be your hardest challenge. thats where having real coon dogs will help. if they tree a few while he is around, he will eventually jump up on the tree and bark with them