Originally Posted by Richard Martin
Take the cap and machine to the Stihl dealer. They will replace the cap for free REGARDLESS of the age of the machine. One of my BR600's is a 2005. My Stihl dealer replaced the cap for free on the spot. No questions asked. Despite someone misinforming me about the new caps being screw in, the newest caps are still of the flip design but quality control in manufacturing has been improved along with a new composition of materials that go into the cap.
The new cap is a huge improvement although I really wish they would go back to the screw in style cap. I was the first person on Lawnsite to raise the alarm about the flip caps back in 2005. I just retired that blower to backup status last week.
Talked to my local Stihl technician today about these caps again and he related something new that I had not heard before. The caps have been redesigned because of ethanol and it's effect on the plastic the caps were originally made from. According to him, the plastic would swell and create the problems of just getting the caps off the equipment (my experience exactly). The new caps are supposed to solve the problem. I have tried spraying the cap, once it's out, with Fluid Film with some success. He replaced one cap the last time I had my trimmer in for repair with a new cap and haven't had a problem since with that one. Hopefully they have fixed the problem for good!!