[HO455]

At no point should "Sanding" the bearing be an option.

Those parts either fit correctly
or they are the wrong part.
or they are installed incorrectly.

The bearings were manufactured to precisely fit a properly machined crankshaft down to .001 thousands. Sanding can only destroy those precise clearances.

All the bearing clearances in your engine are part of a balanced system. The oil pump supplies X amount of oil volume. Each bearing is engineered to bleed a certain amount of that total volume back to the oil pan. If one bearing bleeds too much oil it robs oil from other bearings in the engine. If the bearing clearance is too tight then the bearing overheats and fails.

For example if a high mileage engine is experiencing rocker arm failures it may be due to loose bearing clearances on the crankshaft bleeding off the oil that needs to be forced up to the rocker arms.

There is no way we can help without pictures but ideally you need some experienced eyes and hands on the engine to determine the problem and what the fix is.

I'm not trying to be an a$$ here but it is so easy to turn all those new parts and machine work into scrap iron within minutes of the initial fire up. Trust me when I say you don't want to know the feeling that comes from that.