w124 Smog Air Pump rebuild

[glenmore]

I gather from the threads that the typical problem with these pumps is the bearing in the pulley. That repair is straightforward. There is a fellow on ebay that sells the bearing along with instructions for $50. I am pretty sure that my problem is the inner bearing, i.e. the pump makes noise on startup only and when it clicks off, the continuous running pulley is fine. Anyone replace the inner bearing? Difficult? The fellow on ebay suggests just to relubricate this bearing.

Thanks,

glenmore
1991 300CE
2000 C280
1990 LS400