42. Q. How should you clean the commutator, and when?

A. The commutator should be cleaned before starting out on each trip by

using a piece of damp waste, rubbing the bars lengthwise, then wipe dry

with clean dry piece of waste.

The Traveling Engineers' Association to Improve the Locomotive Engine Service of American Railroads Examination Questions and Answers for Firemen for Promotion and New Men for Employment · 第 297 / 436 题