Re: Force 120 top cylinder dry ? Help
If the top cylinder is dry, either the reed plate is stuck, and I'm not sure how???, or the top carb feeding the top 2 cylinders is extremely lean.<br />I know you say you have spark on all 4 but you cannot simulate heat when testing plugs, and heat causes alot of resistance, so I must ask when was the last time you changed plugs, and can you do a compression check again??<br />Another thought is are you sure the plug leads are going to the proper cylinders. for the engine to be "After-firing" (through exhaust), you have one firing way after it should, as the piston is coming down-ports exposed, but on a 2-stroke, this will usually force some back through the intake as well.<br />This is something you "might" see if the flywheel key was sheared and moved, changing the timing slightly.<br />To check this, pull the top plug, insert a pencil to contact piston and rotate flywheel in the normal direction of rotation until the piston stops, or starts to retreat on that cycle....center the flywheel as close to TDC of the piston as you can, and then look at the timing indicator...it should be within 1 degree of TDC #1...If it is, this would eleminate key shear. Let me know what you find there, and do a comp check if you can....
