I've got a FS 40 weedeater and the cap has separated from the nut causing the cap to fly off. Without the cap, I can't get fresh line to feed and I can't get the cap to stay on the head. Need some help!
If I'm understanding you correctly, it sounds like you need a new bump head? They're available on ebay for less than $10.
There are genuine parts on eBay as well. Yes, $21.95 for the whole head. You can get just the genuine stihl knob for about $10 including shipping.Yeah and there stihl imitation, the real thing is 21.95 on ebay plus shipping, he can go to any Stihl dealer in his area and get the head.