Oh, David, if yur air pump is like my '91, it uses a magnetic clutch like an AC compressor. And it only cuts in for a minute on a cold start, then cuts off and only turns the outer idler bearing. If the pump itself is noisy, just unplug the wire to the magnetic clutch, and it will never cut on (also plug the vacuum signal to the air valve so it won't open and possibly let exhaust back up). If the idler bearing is bad, they can be easily replaced for not too much $$.

DG