Originally Posted by WorkinOnIt
That diagram carb shows the Main Mixture screw BEHIND a retainer ball. The ball is part # 33 and the main mixture screw is part # 34. But, your carb is different. That diagram is for reference only. Do you see what I mean? Both of these parts go in the diagram carb in front of the plug according to the diagram. The jet plug and the O ring for it are listed as a kit at the beginning of the parts list for your carb with the rebuild kit, gasket and diaphragm kit etc. As the EPA regs progressed, we have been able to adjust carbs less and less. Let me know if you get the thing to operate correctly. I have to study the diagram further to see if there is anymore you can do. If the carb sucks air out of that plug hole on the K-66B...do you see anything else at all in there?
The parts list does not include 33 and 34 for my K66B so I think the diagram shows either the fixed jet 18 and plug 21 or adjustable jet 33 and 34. I have not been able to remove jet 18--at this point I've probably ruined the possibility of getting it out--brass screwdriver slot is beginning to wear out from my attempts to get it out.
The trimmer runs great at high speed with this carb, but dies as soon as I let off the throttle. I don't know if this is a prior existing problem. I started it and ran it at wot for maybe 5 seconds before removing the gas and cleaning it up to go in the van for the 900 mile trip back to my house. I should have run it before changing the gas lines and grommet and removing the carb--one of these days maybe I'll learn not to tear down without getting as much running info as possible up front!!!!