PRR "Madison Hill" SD7s

From the PRRT&HS discussion group:

Units 8588 and 89 were special order SD7's built in October of 1953 with modifications that made their assignment exclusive to Madison Hill.  During their years of service one unit was assigned to the hill while the other was assigned to nearby Hawthorne Yard where it was used for switching duty and getting its scheduled inpsections.  They would then switch assignments approximately every two weeks.

The PRR had very strict orders as to how the trains were to operate on Madison Hill, your right a 30+ coal train was out of the question.  Trains could not exceed 15 cars, or 350 tons.  The engine had to be placed on the downgrade side of the train and speed could not exceed 8MPH.  The units had to be inspected by the assigned crew every time prior to being used on the hill to assure all the special appliances (railwashers, etc) were functional.  These units held this exclusive assignment for 25 years, lasting into the PC days.  Conrail later disposed of the units.

If you get an employee timetable for that area you can see the rather lengthy instructions the PRR had for them.

Pennsy was early in modifying its engines equipped with 24-RL air brake schedule to provide pressure maintaing.  Did these two units have the pressure maintaining 24-RL air brakes?

I did hear PC took the teo engines, did some repair work, and sent them back.  Guess they did not know about the hill, and took some stuff off of them.  Caused that "Oh Manure" feel on the first run!

I've also heard, but can't reliably confirm, that these units wound up MU'ed with standard 62:15 units, and thusly caused problems. It would be easy to imagine something like that happening with the PC merger, and the all too frequent information disconnects.   It's difficult to assess what the true weight of these units was, by the time the Penn finished playing with them.  The "book" states that they were rated at 90K worth of TE., which is likely rather conservative. They were rated at 4.5 Min. continuous speed. I knew virtually nothing specific about these two, until the late '60s, when we got into a blab fest with some old Pennsy heads in either Columbus or Marion, about which locomotive could start the heavier train....PRR J1 or AT&SF 5011 Texans.  Answer: neither!  It was the either of the two above mentioned EMD's !   Talk about a shoot down !  However, knowing what I do today, the old heads were probably right !  Never did get to see these guys, but the Bessemer had boat loads of SD7's and nines.  They never had any trouble starting anything, especially the 450's, with their 65:12 gears.  Seems the old EMD salesman was right, when the SD7 came out in 1951...." All the advantages of a Shay, with none of the disadvantages !"  

When any unit/units with 65:12 gearing was/were MU'ed with "standard" 62:15 geared units, the only thing that happened was, obviously the 65:12 units had a lower minimum continuous speed, plus a lower maximum full HP speed, i.e. NOT 60MPH. No "problems" were caused unless the 65:12 geared unit was in the lead, and the Engineer worked the consist down too slow, and paid no attention the the trailing 62:15 unit short time rating.

According to "Pennsy Power II":

Class ES15a Nos. 8588, 8589 built 1953. Changed to class ERS15ax with new Nos. 6950 and 6951. Built for the 5.89% Madison, Indiana grade. Who'd of thought Indiana had a grade like that? Doesn't mention assignment though.

Madison Hill is a severe grade because the railroad is crawling up the side of Ohio River valley. Having seen Madison Hill in the '80's, I was quite astounded with the severity of the grade. Anyone know what the gradient % was? When did the Madison Hill line go out of service?

Built for the 5.89% Madison, Indiana grade.

The Penn evidently thought that there was enough difference in the operating characteristics to spend a tidy sum on re-gearing most of their helper F3s and F7s (EH15) from the late '50s onward, to be consistent with their 62:15 road freighters (EF15). New HD buss cables went in as well. All this work, only to trade 'em in on GP30s shortly afterwards. This came about with the late '57 arrival of the RSD12 Alco helpers, with far greater capacity on the mountain.  PRR also grabbed twenty five SD9s (ES17a) in the same time frame, all with 62:15 gears, even though they were earmarked for service quite similar to the earlier SD7's. They also had MU from the start. There is a long standing story (or rumor) that the 65:12 geared locos were a big headache because the pinion was machined directly into the traction motor shaft....maybe.  I say that because nobody on the Bessemer ever complained about the 450 series for that reason. OTOH, if you busted a tooth on the pinion, you'd have a job to do !   We heat treated scads of SAE4140 motor shafts for GE at Modern/ Erie, and the consistency of the material was all over the map. I imagine EMD had a far superior control over their raw materials...or the whole 65:12 thing would have been a disaster !

This is a really good thread.

The PRR road #s of these units would fit nicely with MPC Lionel  

Not a "story", but true FACT. The 12 tooth pinion was indeed machined directly into the traction motor armature shaft, obviously due to the small diameter of a 12 tooth gear. If damage to the 12 tooth portion occurred, a new armature shaft must be pressed into that armature.  No "maybe" about it.  Those railroads with proper maintenance and care keeping the gear cases tight and filled with crater compound, had no problems with the 65:12 gear ratios.

Yup, it's right there..illustrated in the SD7 operator's manual.  Gear teeth right in the shaft.  You'd think that the need to keep the cases tight, and properly lubed would be obvious, but short cuts get taken...and the price is paid!  Was the Penn guilty of such brainless stupidity?? Gonna guess that it would come down to "who and where".  Being assigned to one home terminal base (Hawthorne) would help, but not guarantee the proper treatment.  I'm going to speculate that the reason for the switch to 62:15 gears on the SD9 order was more a recognition of the higher capacity motors available, plus a desire for standardization.  Good to hear that others besides B&LE had no difficulty with the 65:12 set-up.  I'd be curious to learn when this option was dropped at EMD.

I can't recall that the 65:12 gear ration "option" was ever "dropped". In fact, I believe the Belt Railway of Chicago GP38-2 units may have had 65:12, plus HUGE amounts of added ballast, so as to make them the heaviest GP38-2 units ever produced. Many of the US Steel railroads ordered special increased ballasting also. 

I think the Sales Engineering Dept. eventually had to raise the price so high on the 65:12 ratio option, that no railroad nor industry ever ordered it anymore. Then with the development of AC Traction Motors, and their required helical cut gears, there was no longer a need for the 65:12 ratio. 

When TRAINS did a series about the diesel engine about 20 years ago, it did mention the Belt Railroad of Chicago had "heavy GP38-2's.

Even in the 19th century, this line had special motive power. The Rueben Wells, a prodigious, for that time, 0-10-0 was built for the Madison Hill line in 1868!

Yo, No. 90!  Ahoy !    As for the brakes installed in "James" and "Dolly"....I suspect that whatever options were available to the schedule 24L would have been obtained by the Penn at the get-go. This was still the era where the Penn made a big deal over assigning specific locomotives to specific areas and responsibilities. This would change by 1955, with the mass infusion of GEEP 9s ....good for anything - anywhere. As you can see from other posts, this was about as "hands on" as you get on the PRR.