With regard to the maintenance of electrical generating machines with insulated pedestal bearings, what practice should be avoided?

Correct Answer: Option B — painting or allowing grease build up on the insulated area

Insulated pedestal bearings prevent destructive circulating shaft currents from flowing through lubricating oil films to the hull. Paint, oil, or grease bridges this critical insulation barrier, shorting the isolation path and permitting bearing-destroying electrical pitting per IEEE 45 machinery protection guidelines.