Would you ever find GP7s and GP20s together?

Jeff; I believe that generally speaking, you would have had locomotive consists in the late ‘50’s / early ‘60’s that contained both GP7’s and GP20’s. Mechanically speaking, there is no reason they couldn’t have been operated together in the same consist. Of course, not every railroad took GP7’s nor did every railroad have GP20’s so whether both engine types could / would appear in a consist together would be dependent on the particular railroad.

Curt

PS: A cautionary note. Avoid using a term like “lashup” to describe a locomotive consist on OGR Forum. It will cause a certain publisher emeritus to start wobbling around the room clutching his chest and gasping for air…😉

Yes.

Dave

GP20's was not the most popular GM locomotive made. Far more roads had GP7/9's than GP20's. One that would be likely to have those locos MU'd together are Burlington, New York Central, Union Pacific, Southern Pacific, Milwaukee Road and Western Pacific. More western roads had GP20's than eastern.

@Chuck Sartor posted:

GP20's was not the most popular GM locomotive made. Far more roads had GP7/9's than GP20's. One that would be likely to have those locos MU'd together are Burlington, New York Central, Union Pacific, Southern Pacific, Milwaukee Road and Western Pacific. More western roads had GP20's than eastern.

You forgot the Santa Fe, with the most GP20 units, at 75. GP7, GP9, and/or GP20 units MU'ed together would probably have been quite common on the Santa Fe, Burlington, NYC, etc..

Also, the reason that the GP20, and even the SD24, models were "not as popular" was, The new & improved GP30 came out in 1962.

@Homey B posted:

PS: Technically, it doesn't matter.  The livery that everybody seems to know came into reality in 1974, so all of those early GeePs were probably long gone and certainly would not be sporting the newest colors!

Actually, it seems that quite a few high-hood GP7s made it into the blue and white ROCK scheme. Gobs of photos of them in "Rock Island Line" by Bill Marvel. In at least a couple, they are MU'd with a low-short-hood Geep of some sort, maybe a GP35 (it's hard to tell, because the GP7 is the lead unit).

It is safe to say that GP7/9s could be found in lots of diesel consists up into the 1970's.  They were well built and robust machines that served their original and consecutive owners quite well.  The eastern roads that eventually became Conrail kept these locomotives in service for many years and could be found running with other EMD GP and SD units.  Penn Central and Conrail in particular didn't seem to mind putting them in consists with not only EMDs but also GEs and ALcos. 

As with anything in this hobby, if prototype operations are of interest to you, it pays to do your research.  I'm sure you can find a photo somewhere that shows the configuration you are looking for.

To Hot Water's point, you didn't see a lot of GP20 / SD24s due to the introduction of the true 2nd generation EMDs in the GP30/35 and SD35. 

Further to @juniata guy comment above, I believe the alternative term preferred by some on this Forum is ‘multiple unit consist’.  😉

@PH1975 posted:

I believe the alternative term preferred by some on this Forum is ‘multiple unit consist’.  😉

I believe it's more "correct" than "alternative."

@nickaix posted:

Actually, it seems that quite a few high-hood GP7s made it into the blue and white ROCK scheme.

That just leaves me flabbergasted.  I wonder what the average lifespan of a GP was.  I usually think in years, but miles travelled or hours in service are more useful to machinery.  Considering that ROCK was a smaller operation than any of the huge Class 1 carriers, it would make sense that a 20 year old GP7 might survive with light usage, enough to consider the expense of repainting it.  Oh, and that the railroad was already in trouble and probably had to make the old gear last as long as it could without buying new (or New To Me) equipment.

And, from now on, only MU Consists... 

I started watching a (new to me) CNW video yesterday. The video was originally filmed in 1993. Not only was the Northwestern using former Rock Island GP7’s for switching, there is also one scene where a mainline freight is headed by two high hood GP7’s.

Curt

Re: High nose GP7's into the 70s...

Common as dirt throughout the 70s.

ALL of the regional roads here used them: SLSF, KCS, MOP, RI. Then there were the likes of B&O/C&O, short lines galore, etc, etc.

Andre

@nickaix posted:

Actually, it seems that quite a few high-hood GP7s made it into the blue and white ROCK scheme.

@Homey B posted:

That just leaves me flabbergasted.  I wonder what the average lifespan of a GP was.  I usually think in years, but miles travelled or hours in service are more useful to machinery.

If you're flabbergasted, you may not be considering rebuilds. Railroads rebuilding engines was and is very common, frequently updating them in the process with newer electronics, etc. Often a much cheaper alternative to buying new engines.

@PH1975 posted:

Further to @juniata guy comment above, I believe the alternative term preferred by some on this Forum is ‘multiple unit consist’.  😉

I hate to rain on anyone’s parade, but in real railroading  they could be called……MU/that group/those engines/my train/train 65 or whatever. Only outside of the real train world are terms such a hang up….LMAO

A few more, the old girls/that junk/and last you have to be kidding!

@ThatGuy posted:

I hate to rain on anyone’s parade, but in real railroading  they could be called……MU/that group/those engines/my train/train 65 or whatever. Only outside of the real train world are terms such a hang up….LMAO

A few more, the old girls/that junk/and last you have to be kidding!

Baloney! When I began learning railroading in the late 1950s, and then began working for EMD in 1962, I never, NEVER, heard the term "lash-up" used in the railroad motive departments, nor in train service.

@Hot Water posted:

Baloney! When I began learning railroading in the late 1950s, and then began working for EMD in 1962, I never, NEVER, heard the term "lash-up" used in the railroad motive departments, nor in train service.

You are 100 percent right as I stated

I worked for the railroad as an engineer most of my adult life. never heard a railroader us the term lashup.

To quote Rich Melvin… “Whatever blows your hair back”.

Here's a GP7/GP20, dated 2021.

https://www.railpictures.net/photo/780419/

@Homey B posted:

. . . I am wondering about how EMD engine models overlapped.  In particular, the GP7 and the GP20 . . . what about hauling goods on the rails?  Did the folks who had the older models immediately try to trade up for the better performance? . . .

No.  

By the time the GP20 was offered, GP7 and GP9 units were too new for trade-in unless they were badly wrecked.  First generation diesels were financially amortized over a 15 year period, and that's why you saw FT, F2, F3, Alco and Fairbanks-Morse locomotives often being retired after 15 years of service.  GP7's and GP9's are the "Energizer Bunnies" of the locomotive world; they kept going, and going, and going, long past their 15-year amortization.  Many went through capital rebuilding (and another 15-year amortization) and lots of them remained in service, supplanted on the main line hotshots by higher horsepower units, but still slugging away in secondary freight service as well as yard service.  I can't think of any that were offered as trade-ins, though hundreds have been re-sold through used locomotive dealers after as much as 50 years of service..

In the late 1950's EMD offered an attractive trade-in of FT units, first on GP9's starting around 1956, and then on through GP18, GP20, GP30, and GP35 units, which resulted in the disappearance of almost all FT units.  Locomotives are too expensive to trade in or retire in less than 15 years, except in the case of a very few models that were so problematic that they were too costly to continue using.

Would you find lash-ups made this way?  Could they be made this way?  

Yes.

By the time that the GP20 was produced, railroads had standardized on a single 27-pin jumper cable for multiple unit control*.  This allowed multiple unit operation with other post-1945 EMD's and (eventually) most locomotives from Alco and GE.  FT's and early postwar Alcos used a different number/arrangement of pins, but this was changed by almost all railroads to the 27-pin standard m-u arrangement by the middle 1950's.

* The exception [applicable only for first generation EMD units equipped with dynamic brake] which lasted until the GP20 and then ended, was the EMD field loop cable for dynamic brake control.  This cable was fitted into a rectangular receptacle usually located above the round Multiple unit jumper cable receptacle.  EMD dynamic braking equipped units needed the field loop to control or to be controlled by other units only when in dynamic braking.  Most railroads converted their field loop-equipped locomotives so they could use the "more modern" potential line control for dynamic braking.  Not SP, though.  They ordered locomotives up through SD45's with field loop receptacles and a selector switch for the Engineer to use field loop when m-ued with SP's huge number of unmodified SD9's and GP9's, or to use potential line control when no field loop units were in the locomotive consist.

Also, Union Pacific used a 3-cable multiple unit arrangement up through the mid-to late 1950's.  UP and Northern Pacific had a few sets of really odd jumper cables, to m-u GP9's of both railroads when they operated together on the Camas Prairie Railroad in Idaho, which was jointly owned by Union Pacific and Northern Pacific.  

Some of the very earliest diesels - like EMD FTs - didn't last too long. Due to improvements EMD made in later models, most FTs were traded in by the mid-1960s (still, a respectable 20 year run). Unlike Alcos and some other maker's locomotives, EMDs didn't really have problems and parts were easy to get, so later locos just kept going.

Some examples:

I used to visit BN's Northtown yard once a year back in the 1980s. BN used 1950s hi-hood SD9s to switch the hump. In this century, BNSF was still using the same diesels for the same work. In the 1980s Soo Line was still using hi-hood GP9s, as was C&NW. Some Soo engines lasted long enough to be repainted into CP red in the 1990s.

The F9s Erie Mining Co. bought for their taconite railroad in the 1950s kept working into the early 2000s. Several railroad are still using SD40-2s in everyday service that were built 50 years ago, and GP30s built 60 years ago.

On the Santa Fe in the 80's and 90's I usually worked the Emporia, (or later KC) to Ark City pools, GP7's and GP20's in the same consist happened a lot. The KC-Ark City pool was famous for junk power back then, and if it kept running, it went on through to Texas.

@Number 90 posted:

...... GP7's and GP9's are the "Energizer Bunnies" of the locomotive world; they kept going, and going, and going, long past their 15-year amortization.  Many went through capital rebuilding (and another 15-year amortization) and lots of them remained in service, supplanted on the main line hotshots by higher horsepower units, but still slugging away in secondary freight service as well as yard service.  I can't think of any that were offered as trade-ins, though hundreds have been re-sold through used locomotive dealers after as much as 50 years of service.....

I think maybe this video had been mentioned elsewhere on the Forum fairly recently, but here it is again. Very interesting to watch, and right on point to Tom's comment about GP7s and GP9s going on and on and remaining in service.

https://www.youtube.com/watch?v=FEjWsGbJdGc

@breezinup posted:

I think maybe this video had been mentioned elsewhere on the Forum fairly recently, but here it is again. Very interesting to watch, and right on point to Tom's comment about GP7s and GP9s going on and on and remaining in service.

Every time I watch this one, it makes me wonder "How hard can it be to actually own and operate one of these?  Forget the toys and go 1:1 scale..."

Technically, wouldn't this engine be a GP-35 now that it has the newer engine block and electronics/wiring?  Guess that proves that the external body we see and use to identify a model doesn't have to match the insides.  Yes, you can have a "sleeper" the way they do in street racing.

According to utahrails.net the UP [effectively] converted 66 GP-9s into GP-20s. Intermixing of [especially] EMD locomotive models was/is quite commonplace. Later 567 blocks can be modified (and many were) to accept 645 power assemblies thus extending their viability into the present.

https://utahrails.net/articles/up-gp20.php

@geysergazer posted:

According to utahrails.net the UP [effectively] converted 66 GP-9s into GP-20s. Intermixing of [especially] EMD locomotive models was/is quite commonplace. Later 567 blocks can be modified (and many were) to accept 645 power assemblies thus extending their viability into the present.

EMD two-stroke cycle engines do not have a "block", as it is a fabricated crankcase, i.e. it is NOT cast like a "block". At any rate, any 567C and later engines will easily accept 645 power assemblies, without any modifications to the crankcase itself. However, camshaft counterweights must be changed as well was the blower driveler ratio on normally aspirated engines (non-turbocharged).

https://utahrails.net/articles/up-gp20.php

@Hot Water posted:

Yes, a more precise term would be "weldment" but to most folks their everyday (and perhaps only) exposure is to the cast "engine blocks" used in automobiles. As well, GE, Baldwin and IIRC Alco locomotive engines without exception utilize(d) cast "blocks" so in that regard EMD is the outlier. I've always found fascinating EMD's development and use of weldments for not only engines but for underframes as well in a time when castings were used pretty much universally for locomotive frames.

@geysergazer posted:

Yes, a more precise term would be "weldment" but to most folks their everyday (and perhaps only) exposure is to the cast "engine blocks" used in automobiles. As well, GE, Baldwin and IIRC Alco locomotive engines without exception utilize(d) cast "blocks" so in that regard EMD is the outlier. I've always found fascinating EMD's development and use of weldments for not only engines but for underframes as well in a time when castings were used pretty much universally for locomotive frames.

For what it's worth, the welding technics developed by EMC/EMD became very beneficial during WWII for welding armor on Tanks and some other tracked vehicles. Thus eliminating rivets during construction.