Choosing the correct clearance for a sleeve bearing involves consideration of the speed and load, as well as the geometry and lubricant. You mention blackened oil, but you do not mention whether the babbitt was damaged. Using 0.001 in/in works very well for some applications. Other designs...
You mention damage to the unloaded thrust bearing. What is the form of the damage? Does it indicate loading or is it oil flow related damage? If loading, then clearly, this thrust bearing has load under certain circumstances. What would those operating conditions be?
-- Lyle
