Thanks again for the advice John. Yes, I certainly understand the physics involved as well as the critical importance of correct valve timing on an "interference" type engine. The reason for my question was that I do not have the loader in-hand so I can only hypothesize the function, which I believe prevents the fed chain from coming up and off the sprocket. A "loaded" camshart has significant rotating resistance, thus the potential for a fed chain to jump a tooth...if not held firmly engaged with the sprocket teeth. I believe the the "unloading" of the camshaft by removing the rocker followers would be optional with the chain loader. I was trying to confirm this. In any case, I do plan to use the loader as you recommended. I also will load the chain by manual rotation of the crankshaft. I definately will not have my wife assist me...maybe my nephew who is also, as I am, a Mechanical Engineer.