Center crankshaft seal questions

How tolerant are the labrynith center seals of pitted crankshaft surfaces compared to the standard TC style oil seals? I have a few Cuyuna 428 motors and so far the 2 that I have torn down have had rusty crankshafts. The first one I was able to put back together using multiple redi-sleeves on the crankshaft. I had to use 2 back to back on the center seals. That motor is now down on power, lazy accelerating and does not like to start so I`m worried the center seal is leaking again. The 2nd motor I pulled apart has rusted needle bearings and seal surfaces. I`m going to check victim number 3, but I would like a plan before I dive too far in.

The stock design uses a NOK AW1754E 30X62X14 Seal which is no longer available. I can put 2 standard 30x62x7 TC oil seals back to back, but that does not work well with a pitted crankshaft surface. Since no one makes a redi-sleeve that is wide enough I am considering switching to a labrynith seal like this. Has anyone ever tried switching seal styles on a crankshaft? Any other thoughts?
The labyrinth seal is just a thing with some grooves on the ID that have a small gap to the shaft, it doesn't even touch the shaft and it doesn't actually seal, just makes it so there is small gap with a lot of resistance to flow. I would think it would not matter if there is a little pitting.
Does anyone know how what the standard clearance between the crankshaft and seal is? I picked up a seal from a yamaha 340 snowmobile that uses the same 30x62 bearings so I thought the seal should fit. The outside matches the bearing, but the center hole is 32mm. I know it isn`t supposed to be an interference fit, but I also didn`t expect a MM all the way around.


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