David S,
Has your crankshaft been reground to .010" under? Did you put in a new connecting rod and is it for a .010" under crankshaft?
I don't believe a K321AQS has balance gears so we can cross those off the list. It would also have an electric PTO clutch so I doubt that would be the cause. Check to make sure theres no slop in your driveshaft components and that the rag joints are in good shape on both ends. Could be the rod or a main crank bearing.
Has your crankshaft been reground to .010" under? Did you put in a new connecting rod and is it for a .010" under crankshaft?
I don't believe a K321AQS has balance gears so we can cross those off the list. It would also have an electric PTO clutch so I doubt that would be the cause. Check to make sure theres no slop in your driveshaft components and that the rag joints are in good shape on both ends. Could be the rod or a main crank bearing.