Refurbishing 1958 5.5. Have rebuilt the carb, replaced a coli, drained, cleaned, inspected and resealed the lower unit, replaced fuel lines and turned the (start, slow, fast ) wroding around so its correct. After tappint the bowl to shake loose the needle valve I have finally gotten it started and high speed adjusted, still working on low speed. However, I have a big snag. When the flywheel rotates at a certain spot it is "grabbing" the magneto base plate and turning it, thrusting the throttle to its lowest setting. While running at slow speed it is very difficult to hang on to the handle to keep it running. I thought this was odd while I was trying to start it and now that it is running it creates an impossible situation. I am hoping someone out there has experienced something like this and has an easy fix. I have looked but for the life of me can't guess what is causing this. Coils are both adjusted back and I can't see anything that is rubbing. I am stumped. If needed I can take some pics tomorrow.