Steam & Excursion > MU-ing steamers

Okay we all know that diesels have MU capability, and steamers do not. Or do they?
Questions...
1. Do steam locomotives have the sand/brake hoses tha diesels have? Meaning if 2 steam locos were doubleheading would the lead engineer have control over both locomotives independent brakes and sanders?
2. Is it true that Steve Lee\'s crew has devised a device to MU the 844 and 3985 with a diesel so that the trailing diesels are controlled from an electronic throttle in the steamers cab? I think I read something in a Trains mag once that indicated Steve and his crew were running with the diesels through a tunnel once and the diesels died so they had to throttle up on the 844 to get through the tunnel. The way the story was told indicated the diesels were being controlled by the lead engineer in the 844\'s cab...
CR Dave

Several mainline steam locomotives have the capability to control helper units from the cab of the steam locomotive, provided the helpers are located behind the steam engine. Those that I can think of off-hand that are MU equipped already include:

SP 4449
UP 844
UP 3985
SP&S 700
GCRY 4960
GCRY 18

I\'m sure there are more, but these are all I can think of right now. As for MU pass-through on steam locomotives, I don\'t know if the 3985 is equipped for that, or whether the diesels were being controlled from the cab of the 3985.

BTW, the incident you heard occurred on route to Railfair 99 through Donner Pass. The engines came out the west end of one of the tunnels completely black from their exhaust after having to accelerate inside the tunnel.

pennsylmania wrote:

>
> 2. Is it true that Steve Lee\'s crew has devised a device to
> MU the 844 and 3985 with a diesel so that the trailing diesels
> are controlled from an electronic throttle in the steamers cab?
> I think I read something in a Trains mag once that indicated
> Steve and his crew were running with the diesels through a
> tunnel once and the diesels died so they had to throttle up on
> the 844 to get through the tunnel. The way the story was told
> indicated the diesels were being controlled by the lead
> engineer in the 844\'s cab...
> CR Dave
>
> [%sig%]
765 also had a similar device where 765\'s engineer could control trailing diesels. Steamers cannot be MU\'ed as far as throttles, but brakes and sanders are a different story.

Also...here is a link to photos of the MU system being installed on the 700 last year.

http://www.sps700.org/gall02mu.html

pennsylmania wrote:

> 2. Is it true that Steve Lee\'s crew has devised a device to
> MU the 844 and 3985 with a diesel so that the trailing diesels
> are controlled from an electronic throttle in the steamers cab?

Steve\'s crew is not the originator of the MU device. Doyle McCormack first used one on the Freedom train in 1975. Steve does have control over most of the diesel functions from the steamer cab with the exception of dynamic brakes.


> I think I read something in a Trains mag once that indicated
> Steve and his crew were running with the diesels through a
> tunnel once and the diesels died so they had to throttle up on
> the 844 to get through the tunnel. The way the story was told
> indicated the diesels were being controlled by the lead
> engineer in the 844\'s cab...

The way Bob Krieger told it, temperature in the cab reached 180 degrees on the occasion you mentioned above. By the way, Roger Myli told me last Thursday that on the initial run into Denver, temperature in the cab reached only 128 degrees.

jdc3751 posted a link to the installation process of the MU wiring on the SP&S 700. Here is a picture of the MU control stand. The MU control on several steamers is capable of motoring control only on trailing diesels. The 700 is one that can also control dynamic braking on trailing diesels.

---

Frisco1522 also has a MU box which controls the throttle of a trailing diesel unit (s). The auxiliary water car has feed thru MU cables so the diesel can go behind it.
We only used it briefly before the BNSF Employee Appreciation Special in 2001, and used it quite a bit for that. Came in handy getting up to track speed quicker, then cut the diesel back to idle and maintain with the 1522. The dynamic feature would have been handy. The diesel was nice in that we used it\'s air compressor and saved wear and tear on the 1522\'s.

Thanks for all the replies! I find modern technology on steam locomotives very interesting. Don\'t several of these steamers also have air horns?
CR Dave

I know the SP locomotives (e.g. 4449 and 2467, not sure about 2472) have air horns, but they were installed when the engines were still owned and operated by the railroads.

Back in the 70\'s, the Clinchfield 1 had an MU arrangement to a diesel helper "B" unit that was disguised as a baggage car.

jdc3751 wrote:

> I know the SP locomotives (e.g. 4449 and 2467, not sure about
> 2472) have air horns, but they were installed when the engines
> were still owned and operated by the railroads.


The 2472 does not have an air horn. I do not know if she ever had one. The 2467 does, and it was moved to a place under the front of the running board on the fireman\'s side, just behind a cut-out of a very nice SP herald. (The 67\'s crew did not like the looks of the horn wher it had been on top of the boiler somewhere.)

Margaret (SP fan)

Here is a picture of the 2467 back in 1955 with the air horn mounted in front of the stack. From pictures I have seen, several other SP locomotives had airhorns in that same location.

David L.

---

It might be fun to try to design a servomechanism that could control a steam throttle! Man, can you imagine the claptrap that would be involved? I suppose some purist would suggest that you just remove the throttle handle and install a servo motor at the hinge point. Then it wouldn\'t be any fun to be in the cab.

nycman wrote:

> It might be fun to try to design a servomechanism that could
> control a steam throttle! Man, can you imagine the claptrap
> that would be involved? I suppose some purist would suggest
> that you just remove the throttle handle and install a servo
> motor at the hinge point. Then it wouldn\'t be any fun to be in
> the cab.

Yeah, how could you ever get the feel of overcomming the resistance of the closed throttle against the steam..

or, the knowledge that you are getting everything possible out of the engine as you increase it to the point when you feel the throttle suddenly floating to your touch. Then, you know it\'s time to hook up the Johnson bar a notch or two...

Nope. A servo just won\'t give you the feedback you need to get optimum performance out of the engine!

nycman wrote:

> It might be fun to try to design a servomechanism that could
> control a steam throttle! Man, can you imagine the claptrap
> that would be involved?

I believe the Union RR\'s 0-10-2\'s (built in 1936) had such a mechanism, controlled by pneumatics, and mounted on the right side of the steam dome. I was never in the cab of one of these, but I\'ve had a reliable source who was in the cab of one on the DMIR, and he said it had a control stand that looked like an early EMD drum controller.

jdc3751 wrote:

> I know the SP locomotives (e.g. 4449 and 2467, not sure about
> 2472) have air horns, but they were installed when the engines
> were still owned and operated by the railroads.
>
> [%sig%]


Milwaukee 261 also has an air horn. It sounds like an RDC when it blows for a crossing.

MTMEngineer wrote:

> Yeah, how could you ever get the feel of overcomming the
> resistance of the closed throttle against the steam..
>
> or, the knowledge that you are getting everything possible
> out of the engine as you increase it to the point when you feel
> the throttle suddenly floating to your touch. Then, you know
> it\'s time to hook up the Johnson bar a notch or two...
>
> Nope. A servo just won\'t give you the feedback you need to
> get optimum performance out of the engine!
>

Too bad there ain\'t of the hi-tech boys out there willing to give it a shot ...if they can control rocket motors on a big Saturn to the moon a steamer ought to be a piece of cake!

Actually, the Great Western Railway in the UK used such a system on branch lines. The "auto coaches" had a cab car that the "driver" used when "pushing". When "pulling" he\'d be in the loco cab. Of course, the fireman was always in the loco cab hand firing the coal. I believe the used 0-6-0\'s for motive power. There\'s one on display at the transport museum in London and at least one preserved railway is restoring one.