I am a newbie and interested in advice in giving my backpack blower ( Stihl BR340 ) a mini tune-up. Aside from replacing the plug and air filter what would you recommend ? I have two complaints currently with how it's performing. First, when I start it I have the play with the throttle for about 20 seconds or else it will stall, it sort of bogs down and I have to give it some juice to keep it going. After 20 seconds or so it runs like a champ. My second complaint is that after running it for a long period of time ( say 45 minutes ) if I shut it down and then try to re-start after 5-10 minutes it takes forever to try and get it started again. On a cold start it starts on the second pull, put after it's been running for sometime it takes a 15-20 pulls to get it going again. Thanks for the advice.