The engine sprocket bolt on my 2009 G5 is a "right hand thread" (clockwise to tighten). I am under the impression that on later model UCE engines this was changed to "left hand thread" (counter clockwise to tighten). If this is true when was the change from RH to LH thread for engine sprocket bolt made? Can one tell by the engine number? Did they also make this change for the nyloc nut on the clutch shaft or is it RH thread on all UCE engines? Of course i could be totally wrong about this, as is often the case - just ask my wife!
Story i heard somewhere is that the bolt/shaft thread direction was changed as the RH threaded bolts holding sprocket on could come loose, as mine did. Fortunately when i heard a sound like squirrels had stored nuts inside the LH cover i took it off and found the bolt rolling around before it did any damage, and replaced bolt using blue loctite.