I'm Bill Elzey with Showplace Lawns. How to tune a gas trimmer. Tuning is very simple. You would change your spark plug. Take the old one out. Some mechanics will tell you different but I always believe that you need to put a rag and sort of wipe out that spark plug hole a little bit. Put a new plug in. Make sure that your wire fits snug to the top of the spark plug. Replace your filter, and make sure that when you have the filter out that you clean the housing that the filter sits in. Replace that. The other thing I would suggest is to use a can of carburetor cleaner and just spray the areas and wipe 'em off in and around the filter, and then spray your carburetor areas and let them sort of drip dry. And, basically that's it for a tune up.