Rebuilding of K's, K2's, and K2a's

nw-mailing-list at nw-mailing-list at
Sat Jun 19 22:50:11 EDT 2004

This is only an opinion, but my guess is that N&W did not give the rebuilt K's
cast steel frames or front end throttles because they did not figure that
those improvements would be cost effective. You will note that the rebuilt
Y5's kept the throttles with which they were built. They could put roller
bearings on all the engine azles of the rebuilt Y5's because the new cast
frames were designed to accept the roller bearings. Apparantly the relative
maintenance costs for an original Y5 and a Y6 convinced the company that
putting cast frames and roller bearings on the Y5's was cost effective.  On
the other hand, it would appear that broken frames was not a big problem with
the K's. Keeping the original frames, it would have been tough to fit roller
bearings to the driving axles. The trailing trucks on the K2s and K2as did
eventually get roller bearings (although not in the initial rebuilding). What
the K's did get was an extensive mechanical lubrication system, and the
rebuilding also included new cast steel cylinders. (for most of them. It
appears that two K1's did not get the new cylinders.)
      It is significant to note that the 45 S1as built by Roanoke in the last
days of steam did not get any roller bearings, while all new road engines
built during the same period got roller bearings on all axles. They did get
Hennsley (sp?) lubricators on all driving axles. Roller bearings on steam
switchers were rare. The only ones that come to my mind were the ones used by
the W&LE.    Jim Nichols

N&W Mailing List wrote:

 > I am aware that the N&W made many improvements to it's mountain type
 > locomotives over the years, thus improving their performance and extending
 > their useful service lives.  However, I am wondering why the N&W motive
 > power officials did not approve of two improvements in particular that I
 > believe would have made the performance of these locomotives even better.
 > These are the cast steel frame and front-end throttle.  I realize that the
 > N&W while thrifty, was also cash rich, and these improvements would
 > probably not have cost any shareholders their dividends.  Is there any
 > motive power department literature, or correspondence pertaining to the
 > pro's and con's of including these upgrades in the rebuilding
 > programs?  What about fully equipping all engine and tender axles with
 > roller bearings?  I respect Roanoke's work and the K's but I was curious
 > why these improvements were not made.
 > Sincerely,
 > Nathan Driscoll

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