Small Engine Problems? Ask an Engine Mechanic for Answers ASAP
Hello and welcome to JustAnswer! My name is***** a technician with over 10 years of experience, and I'll be assisting you today. Sorry to hear your having issues, please stand by while I look into the problem for you, this is not an immediate service however I will try and respond as soon as possible.
The parts which make up your impact driver can be seen here, it sounds like the retaining ring may be at fault, in essence stripping down the gear box or replacing the entire gear box (item 45) is the best way to resolve this issue.