i think all the j’s were built almost identical, but beginning with 605, there is some sort of “horse shoe” looking piece that wraps around in the valve gear area behind the cylinders and down around the main rod. is this some sort of brace that was added after the first 5 were built? the earlier ones never had this…[?]
Steve,
J’s 600 - 604 were built with a “Multible Bearing” Crosshead and Guide (one guide). J’s 605 - 613 were built with the “Alligator” style Crosshead and Guides (two guides).
There were other subtle changes that took place over the years. I would suggest that you find a copy of Ken Miller’s book, N&W Class J The Finest Steam passenger locomotive.
thanks jim, i have the book, but didnt find out, or missed, this info. always wondered what that “hook” was for. its an excellent book by the way. thanks again…
The first five, 600-604, had the multiple bearing crossheads. All the rest had the Alligator crossheads, and the “hook” as you call it was a thing called the “guide yoke”.
The guide yoke supported the guides on the back end. The multiple bearing guide had a center support at the front of the valve gear hanger that was much less obtrusive.
The last three, 611-613, had a different design of Commonwealth tender truck from the others. The last five class A 2-6-6-4s (1238-1242) had the same design of tender trucks. The first eleven Js and the first 38 As shared the older Commonwealth tender trucks. Before you look it up, you might find out that class A 1201 was built with Buckeye tender trucks. These were swapped out for Commonwealth trucks early in its life.
Old Timer