So after using the trimmer for about an hour today, (it is somewhat useful) I noticed something that I haven't before. When the trimmer is in the normal position, that's when it doesn't rev up to full speed without bogging and almost stalling. When it's sitting on the ground (when I'm adjusting the high speed screw) it revs up pretty good. When I have it rotated 90 degrees from normal to edge along the sidewalk it works well too. After I realized this I turned it upside down and it also works pretty well. This I thought was strange. It has nothing to do with the fuel filter not being in the fuel because I checked for that. What else could cause this?
The reason I haven't bought the rebuild kit for this yet is that I don't know for sure that it is going to fix it. I remember reading that there is a non serviceable check valve somewhere inside the carb. Also, if I can't remove the high speed screw, how do I really get this carb completely clean? Should I just buy a new carb?
Has anybody experienced something like this and just had to replace the diaphragms to fix this?
Thanks for all the responses so far.