Steam & Excursion > Steam Files - PRR #10

PRR 5399
Class K4s
 
This locomotive was built by Altoona’s Juniata Shop in 1924 and ran for 15 years as an ordinary unremarked member of the K4s class. In 1939 it was sent to Lima Locomotive Works to receive Franklin Type A Oscillating Cam poppet valves. This conversion was worked on over the summer with Ohio Steel Foundry of Lima providing the half saddle cylinder castings. When it was released for service on September 7, 1939 the results were found to be outstandingly successful.
 
Compared to a standard K4s, the drawbar horsepower was 44% greater at 80 mph and 54% greater at 90 mph.  It handled a 1000 ton train at 94.7 mph on level track and could accelerate that train from 40 mph to 75 mph in 288 seconds, five minutes and 5.5 miles less time and distance than before rebuild.
 
As a result of all the tests, PRR, Lima and Franklin Railway Supply felt even more was possible and during the Summer of 1940 more refinements and improvements were made.  A new larger superheater, multiple front end throttle, and enlarged dry pipe were part of the program giving greater steam flow. It was placed on the Altoona Test Plant and found to be able to evaporate 77, 480 pounds of water into steam in an hour. It was also the first locomotive on the test plant to run continuously at 100 mph for 30 consecutive minutes and attained a machinery efficiency of 95.6 %.
 
In the early 1940’s it was PRR policy to double-head all K4s’s on the name trains west of Crestline, OH if they were over 12 cars, but the 5399 was allowed to go single with fourteen.
 
One more improvement was made during the Autumn of  1942 when 5399 was equipped with a high speed (up to 35 mph) booster engine on the rear truck. Truly a “Super Pacific” had been created. The locomotive seems to have served well and improvements made to it influenced future locomotive policy that led to the Oscillating Cam T1’s we saw in our last installment of the Steam Files. In 1940 K4s 5436 was also equipped with poppet valves, the invention of L. D. Young of the PRR test department. This installation was however not successful and it was quickly converted back. I did a little digging, but couldn’t find anything related to how it worked, or a patent. Perhaps someone else knows or can find that information. Later, K4s 3847 was equipped with Franklin System of Steam Distribution (FSSD) Type B Rotary Cam valves. It apparently was successful, but I haven’t found any test specifications or other info on that application.
 
PRR 5399 was retired in November 1953, a truly remarkable locomotive.

Image from the Steam Files shows the 5399 at an unknown location, probably at the end of its career.
Photographer unknown.
 



Edited 1 time(s). Last edit at 06/30/25 08:09 by train1275.

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Fascinating information.
Bob

The December 1980 issue of Trains Magazine included an article by the late Professor George Hilton about Englewood Union Station in Chicago, particularly his reflections from railfanning there during his youth in the 1940s.  Hilton included separate descriptions of each of the four railroads that served Englewood: PRR, NYC, Nickel Plate, and Rock Island.  

In the portion devoted to the PRR, Hilton particularly noted the variety of special and unique engines that the Pennsy was using on its passenger trains.  As mentioned in these postings, the PRR was experimenting and searching for a less-costly steam-era replacement for the double-headed K4s that led the east-west name trains.  The "Big Engine" and the steam turbine were two such examples, but he also mentioned a K4s that had been modified with Capriotti valves, adding that the crews dubbed this engine "Mussolini."  I don't have the article with me, but Hilton said that this engine frequently went out on its own, leading trains that were one or two cars longer than the usual limit allowed for a single K4s.     

Is this the engine with the Franklin valves that you all are speaking of, or was it a different engine?

As an aside, the other night I was revisiting Edward M. DeRouin's splended book The Pennsy in Chicago and once again came across a sidebar "An Early Quit for Christmas," which described an incident that reportedly occurred on Christmas morning in 1946.  The freight train CO-2 was ready to go at 59th Street with a holiday-shortened consist of 45 cars, and the train crew showed up early, hoping for a fast run and early quit, only to discover that CO-2's power will still out on the road and hadn't arrived yet.  CO-2's engineer called the roundhouse and learned that a K4s was available, so he accepted the passenger locomotive with the condition that a yard engine give them a shove out of 59th Street.  The train apparently made excellent time to Logansport, apparently to the consternation of its conductor, who was unable to do his paperwork in the cabin car and had to wait until the run tied up in Logansport.       

I suspect Hilton might have been referring to the PRR 5699 with Caprotti gear dating to 1929. This was a K5 Class 4-6-2.
Caprotti gear was furnished to the U.S. market by Baldwin as the licensee.

Great story about CO-2's fast run !!



Edited 1 time(s). Last edit at 06/30/25 08:43 by train1275.

>>>Summer of 1940 more refinements and improvements were made.  A new larger superheater, multiple front end throttle, and enlarged dry pipe were part of the program giving greater steam flow. It was placed on the Altoona Test Plant and found to be able to evaporate 77, 480 pounds of water into steam in an hour. 

Wes I miss you my friend.

Explain multiple front end throttle please.
 

Tominde Wrote:
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> >>>Summer of 1940 more refinements and
> improvements were made.  A new larger
> superheater, multiple front end throttle, and
> enlarged dry pipe were part of the program giving
> greater steam flow. It was placed on the Altoona
> Test Plant and found to be able to evaporate 77,
> 480 pounds of water into steam in an hour. 
>
> Wes I miss you my friend.
>
> Explain multiple front end throttle please.


I believe they may be referring to the American Multiple valve Front end Throttle, which is made up of 6 or 7 large diameter poppet valves. The poppet valves have a stirrup on the bottom and are opened and closed by a "camshaft" having fingers which fit into the valve stirrups. Rotation of the "camshaft" first opens the small pilot valve, and then opens, one at a time, the remaining valves. There is probably good photos and descriptions in Locomotive Cyclopedias.

 

train1275 Wrote:
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>
> Great story about CO-2's fast run !!

There are other stories about K4s engines on freight. I've heard a few about them east out of St. Louis. They did better than one might expect overall. On the St. Louis line, the big challenge was Collinsville Hill up out of the Mississippi flood plain. The saving grace was that it is a long, gradual grade, not much curvature, with a pretty good stretch on the flats of a few miles between Exermont and Caseyville to get a run for the hill. If they got a shove out of East St. Louis for some help on the hill, they could do okay with a shorter train the rest of the way to Terre Haute, even on some of the sags further east near Casey, Illinois.

MC

HotWater Wrote:

> I believe they may be referring to the American
> Multiple valve Front end Throttle, which is made
> up of 6 or 7 large diameter poppet valves. The
> poppet valves have a stirrup on the bottom and are
> opened and closed by a "camshaft" having fingers
> which fit into the valve stirrups. Rotation of the
> "camshaft" first opens the small pilot valve, and
> then opens, one at a time, the remaining valves.
> There is probably good photos and descriptions in
> Locomotive Cyclopedias.

I believe HotWater summed it up correctly.
I poked around, and these are the only drawings I can find. Not exactly what I was looking for though. Seems like there was an issue of R&LHS Magazine with a good article about 30 years ago among probably old Locomotive Cyclopedias.



Edited 1 time(s). Last edit at 06/30/25 18:05 by train1275.

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Interesting: I learn something new every day.

Question: do the numbered figures on the left side of the graph denote horsepower output?

NYC_L4a Wrote:

> Question: do the numbered figures on the left side
> of the graph denote horsepower output?

Yes, cylinder or indicated horsepower as opposed to drawbar HP in this case.

Couple of things I've wondered about.
On the older engines et al, were they grease cake lubricated? I never hear much mention of roller bearings.
For years, what kind of numbering system did they use? Reminded me of one of the Bingo cages that whatever number came out was the number of the new engine.
I've heard many stories from Joe Collias who would be out photographing about doubleheaded K-4s at Caseyville or Washington Park "running like the hammers of hell". I was born 10 years too late!

Frisco1522 Wrote:
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> Couple of things I've wondered about.
> On the older engines et al, were they grease cake
> lubricated?

> For years, what kind of numbering system did they
> use? Reminded me of one of the Bingo cages that
> whatever number came out was the number of the new
> engine.

> I've heard many stories from Joe Collias who would
> be out photographing about doubleheaded K-4s at
> Caseyville or Washington Park "running like the
> hammers of hell". I was born 10 years too late!

Grease cakes.

I have no idea on the numbering system. Any Pennsy fans out there that can explain it ?  I think so far Frisco1522 has summed it up as well as anyone.

 "running like the hammers of hell"  - good old fashioned gut busting run as fast as you can make the wheels turn railroading and and let the cinders fall where they may !

I guess I was born 50 years too late.



Edited 1 time(s). Last edit at 07/01/25 12:28 by train1275.

I was told by a Pennsy fan that the reason PRR steam loco numbers were all over the map was that the Pennsy just used a loco number from a scrapped loco for a new loco. It had sonething to do with how they kept track of their assets.

How would I know, but it wouldn't surprise me if very few K4s received roller bearings, as this was the road that ran many without stokers.

Victor Baird

Posted from Android



Edited 2 time(s). Last edit at 07/01/25 18:55 by wabash2800.

I believe K4 #5371 received roller bearings. 

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dcoursey Wrote:
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> I believe K4 #5371 received roller bearings. 

Roller bearings on the rods but, what about the axles?