That Pesky EMD v GE Thing

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Postby NRECer » Thu Apr 21, 2005 6:19 pm

To the best of my knowledge, the issue of synchronous slip first surfaced on the NYC in the early 60's. I believe the culprits were some 2000 hp Alco road units.

When word got back to the GE people, the answer was-in a word-'impossible.'

Think that the NYC's own Research Dept. ( which was staffed by some very sharp folks) set up and ran some tests to gather the required evidence.

This was before the U25's showed up on the scene.

Postby thebigc » Fri Apr 22, 2005 7:38 am

LCJ wrote:I never quite "got" the reason for 16 notches -- especially when the ammeter went all over the place when you changed positions on the throttle. Were they trying to make it look as if the controls were more precise?

Will -- I like your website.

GE must have thought the 16 notch throttle was what made the E-44 run so well.

LCJ wrote:And -- the U25s were notorious for sucking exhaust fumes into the cab when the heat blower was on. I hated that. In cold weather your choices were leave the window open and freeze, or close it and get a roaring headache.

Those hot-water style heaters on our U-34-CHs were awesome! Much better than those noisy element heaters on our EMDs. You know, the ones you have to get on your hands and knees to see what position the blower switch is in. And while you're down there, might as well adjust the seat just right.
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Postby Typewriters » Fri Apr 22, 2005 8:41 pm

World diesel locomotive expert Steve Palmano has corresponded with me, via my Locomotive Enthusiasts Forum, with supporting information about the exact progression of dates of the previously mentioned GE controllers, and with this information plus some intuitive educated speculation using my collection of GE materials, I've worked out the following rough data, which of course is open to addition from anyone with exact info.

Up until 1/68, GE employed the three-lever stand, which is the familiar long-throttle 3-handle type.

After that time, GE changed to the new, blocky two-lever control stand, which contained a 16-notch controller.

At some point between 4/69 and 9/69, GE replaced the 16-notch controller with an 8-notch controller, while using the same stand. Some units during this time also received the contemporary EMD controller of "three lever" type, with throttle, reverser and ratchet type selector.

In 1972, GE changed to using the AAR compliant control stand and corresponding master controller. The "optional" controller -- which was the aforementioned EMD pre-AAR type, with either ratchet selector or three position selector, was still offered.

To the best of my knowledge, from previous postings here, the GE numbers for these controllers in order was KC-99, KC-102 and KC-108.

Again, if anyone can improve on this, please do, as I've been "after" this kind of data for a while -- and I think you're out there!!!

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Postby LCJ » Fri Apr 22, 2005 11:47 pm

Thanks, Will.

Typewriters wrote:Up until 1/68, GE employed the three-lever stand, which is the familiar long-throttle 3-handle type.

This was one of the most user unfriendly arrangements ever, in my experience. It was a real muscle builder! The only way to make it better was to remove the tension spring on the throttle notch mechanism. Many of us did this regularly -- especially if there were any switching to do. I always replaced the spring at the end of the tour -- some did not.

The reverse lever was a lengthened version of the flat Alco reverser lever.

Typewriters wrote:At some point between 4/69 and 9/69, GE replaced the 16-notch controller with an 8-notch controller, while using the same stand.

There were actually a couple of forms of this set up in regard to the reverser and dynamic brake control. On the earlier one, the reverser had 5 positions, all in a straight line. All the way back was dynamic braking in reverse. Next forward was motoring in reverse. Center was neutral, then motoring forward and dynamic forward. The reverse handle was a thin, long rod with a round knob on the end. A locking mechanism on the handle had to be pulled outward to allow entry into dynamic braking in either direction.

A later version (found on NYC/PC U33Bs) had a shorter lever with a small roller located on the end that was inserted into the slot. There were still 5 positions, but in order to move the lever into dynamic for either direction, you had to lift it up over a raised detent and then it dropped into the d/b position.

Conrail's U23Cs, built in 1970, were equipped with standard EMD, red plastic handled controllers w/o the selector, since they had no dynamic braking.

Postby Typewriters » Sat Apr 23, 2005 2:36 pm

Very interesting! If anyone else can add, please do!

You don't suppose the difference in selector/reverser design corresponded in any way to 16-notch or 8-notch throttle, do you? I note, looking at a roster of PC U33B units, that some were built in late 1968, and that another batch was built in May and June of 1970 -- meaning that if my findings are correct, you'd certainly have some with 16-notch and some with 8-notch throttles.

I had forgotten about your "field modification" on the three-lever controller, and I'm glad you reminded me of it!!!

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Postby LCJ » Sat Apr 23, 2005 5:07 pm

Typewriters wrote:You don't suppose the difference in selector/reverser design corresponded in any way to 16-notch or 8-notch throttle, do you?

Probably so. The earliest of these units were, as you know, ordered by NYC before the merger, some delivered before '68, I believe (not sure).

The control stands had a flimsy fiberglass front on them that didn't hold up very well. The eventual switch to a mostly steel AAR stand was a big improvement for GE. The EMD/AAR style of stand also provided a great place to put a cup of coffee -- on the little shelf in front of the gauges.

Re: That Pesky EMD v GE Thing

Postby Typewriters » Sat Nov 24, 2012 2:06 pm

Note: Resurrecting a LONG dead message string here with a bit of newly discovered information.

In the previous message string from 2005, I mentioned that Steve Palmano and I had formed what we thought was a good progression of dates at which GE changed its control stands. I've just been lucky enough to obtain a rather unusual GE operating manual that nails down one of the dates more exactly.

The manual is a copy of GEJ-3844, which normally is the operating manual for just the U30 series locomotives at the time that they were being offered concurrent with the U28 and prior to introduction of the U33. However, this manual has an addendum (which in GE operating manuals are pink pages) in the back; this section is GEJ-3857, "Operating Instructions Supplement - Model U33 Locomotive" and is dated 11/67 with a print run of 1000 copies.

The only content of this addendum is depiction of, and description of, the two-lever control stand as discussed in this string by LCJ. We can safely assume then that this stand appeared for production U33 locomotives; I briefly looked at some of the SCL U33B photos on Fallen Flags, and these very early units appear to have the two lever stand. The very early D&H U23B units also appear to have this stand. We might then fairly safely assume that the two-lever stand became the GE standard at this time -- 11/67 -- unless some railroad special-ordered the previous KC-99 controller and stand.

The dates of conversion from sixteen notch to eight notch setup on the two lever control stand remains fixed at 4/69 to 9/69 as assumed before. The inclusion of EMD master controllers in the two-lever stand was noted by LCJ as a GE factory option. The change to the AAR control stand and KC-108 controller remains assumed as before.

Finally, for those real rivet counters out there -- it is of interest that the U33 supplement for the U30 manual (thus effectively converting the manual to cover both models) has a GE manual number HIGHER than that used for the manual that covers U23-U30-U33, which is GEJ-3856. It would seem as if GE developed the new manual and this supplement at the same time, and got by with 1000 copies of the supplement tacked into U30 manuals (for U33 locomotives) until the first GEJ-3856 manuals were ready.

I've detailed the U25 control stands on our blog, but have not progressed beyond that point. Click here to see U25 stands from prototypes through final U25 production: ... tands.html

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Re: That Pesky EMD v GE Thing

Postby Allen Hazen » Mon Nov 26, 2012 7:15 pm

Will Davis--
I have no intelligent or helpful comment to make, so I was undecided whether to post at all. But: THANK YOU! At their best, the forums are one of the best (one of the only?) resources for people seriously interested in the details of railroad history. And your reviving of an old thread when you have found new information is, I think, an instance of at its best!
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Postby CREEPING DEATH » Tue Dec 04, 2012 2:28 pm

nickleinonen wrote:the GE engine will make full power even with a cylinder down, the emd most likely will not... [i've seen a 16FDL make full horsepower with #8R conrod broken in half and the piston jamed in the liner... had 5' flames out the stack, but it made full 4400hp under selfload... and a very violent engine viberation


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Re: That Pesky EMD v GE Thing

Postby Engineer Spike » Sun May 18, 2014 11:40 pm

I have some questions about EMD units of the same vintage as the U series. Before this gets moved, the reason is as a side to side comparison.

What type of wheel slip systems did the 30 and 35,series have? How did they compare to GE?

What actuated them, since GM did not use the axle alternators?

How did IDAC work, and what made it better or worse than GE?

To repeat, I know this is a GE page. Since the topic is EMD vs. GE, it would be educational to really compare them. Let's see where each brand was successful or not.
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