I take it the shaft goes to the compressor, correct? If so (I've never worked on a DT 466 yet), then if it's like other compressors I'm familiar with you're better off getting a replacement and reconnecting the gear to that one. Forget about rebuilding that one altogether. My suspicion is you need to do an oil sample from the engine to see if you have shavings in the oil pan coming from somewhere. Get a kit, get the sample, and send it off to be analyzed and make your next best move from there. My gut instinct is telling me you may have serious engine trouble. Compressors usually don't just don't fill up with shavings and lock up without something else going wrong inside the engine first.
Just my two cents.
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