String Trimmers

I just bought a 223L trimmer and fell in love with it after the first two minutes of using it. I can't believe the power it has for being so lightweight. After about 30 minutes it started burning my right forearm. I mean REALLY burning it. Is there some way to remedy this? Is it missing a heat shield? Can I put some sort of heat tape under the plastic housing. When using it, sometimes my forearm rests near the air cleaner and the plastic is soo hot it burns. Thanks for any help. I meant to take a pic of my arm, but forgot.