My 216 was running fine, smooth as a modern engine until it started knocking. A good friend diagnosed a worn rod bearing. Didn't find much shavings in oil. Cylinder 4 had about 1mm play all others were tight but another had a little side to side play. My question is, will I have to have the Crankshaft worked on besides putting new bearings? Also, the bearing was melded pretty good on to the rod. Does an engine shop have to machine those out? Will I have to take the affected piston? Any information on what additional work should be done while I'm at it would be greatly appreciated. Thanks to all.