Small Engines (Lawn Mowers, etc.): Stil Leafblower, leafblower, muffler

Question
I have a Stil leafblower that is hard to start. What I have done to check problem is removing the exhaust and checking the ports -- are good. After removing the exhaust, I started the motor and it runs good - low and high. After installing the exhaust its hard to start and run. The screen is clear and clean. Any ideals

Answer
If it runs great without the muffler, but you have difficulty with the muffler on it, I would look at replacing the muffler.  

Can you clean the muffler to be sure you dont have any plugged ports?

Generally when these units have a problem it is in the carb, not the muffler.  Make sure you have clean fresh fuel.