Re: K-27 valves converted in stages . . .

Russo Loco Wrote:
-------------------------------------------------------
> SebJ Wrote:
> --------------------------------------------------
> -----
> > Yes Casey it is known that 456 remained for
> some
> > time with piston valves and Stephenson valve
> gear.
> > During my researches, I read somewhere on NGDF
> a
> > post from Earl quoting a D&RGW paper with a
> hand
> > written note about that with #456, but that some
> pic-
> > ture proof was still to be found.
>
> > So thank you Bruce, it is the first time I've
> seen
> > a picture of it !  
>
>
> I'll second that motion -    
>
>
> It appears that the first engines converted to
> superheat, which for various reasons pretty much
> requires piston valves, were #454, #456, #458 and
> #461 (not necessarily in that order), and that
> this was done before the obvious advantages of
> Walshearts valve gear over Stephenson were
> apparent, so the new castings for the cylinders
> were made with the piston valves inboard of the
> pistons so that the valve stems aligned (more or
> less) with the existing Stephenson gear. 
> Subsequent conversions to superheat and piston
> valves were done to accommodate a change to
> Walshearts at the same time, so the new castings
> were made with the piston valves outboard of the
> pistons.  When #454, 456, 458 and 461 were
> later converted from Stephenson to Walshearts an
> extra crank was added to the linkage to avoid the
> considerable extra expense of casting yet another
> four pairs of cylinder blocks.  (See
> [ngdiscussion.net]
> 09742 for a simplified drawing of the valve gear
> for these four engines.)

The first 2 engines to be rebuilt were 453 and 455. All received the complete package of boiler work and running gear modifications in the last quarter of 1925. 464 got new running gear, but no boiler work.

Concerning 454, 456, 458 & 461, the only repairs listed are installation of superheaters in 12/28 (454 and 456), 9/27 (458) & 2/27 (461). There is no record of installation of Walschaert Valve Gear or piston valves. The drawing I have for a K-27 (125) with inboard piston valves and Stephenson gear is dated 1918, so one can probably assume that is when they piston valves on those show up. The remaining question is when the new valve gear went on. The records in the AFE book start in 12/1919, it they may have had valve gear installed before then. However the pic of 456 and 464 doubleheaded dates from after 1923 (because of "Western" on the tenders), and 456 still has Stephenson gear. More mysteries.

Some of the engines were done piecemeal, others had the complete job done at once.

engine.............Piston Valves............Superheater

452..................11/30/25....................6/27/28
453..................9/30/26......................9/30/26
454....................................................12/31/28
455..................12/31/25....................12/31/25
456....................................................12/31/28
458.....................................................9/30/27
459..................8/15/27.......................8/15/27
461.....................................................2/28/27
462..................8/31/29....................................
463..................6/30/27.......................6/30/27
464..................9/30/25.......................6/27/28