Steam & Excursion > Question about 3985, 4014, other articulateds

Large locomotives like the 3985 and 4014 have front and rear engines. Is it possible to move the locomotive using just the front or just the rear engine?

I ask because some of the reasons people state that diesels are run with steam excursions are extra power (not going to be a problem with 4014) and reliability. I don't recall many instances when a steam excursion caused traffic delay due to a steam locomotive issue, but the question is could the front and rear engines be considered a redundancy for the sake of reliability, being able to bring in a train with just one engine if the other breaks and avoiding the diesel altogether?

puddlejumper Wrote:
-------------------------------------------------------
> Large locomotives like the 3985 and 4014 have
> front and rear engines. Is it possible to move
> the locomotive using just the front or just the
> rear engine?
>
> I ask because some of the reasons people state
> that diesels are run with steam excursions are
> extra power (not going to be a problem with 4014)
> and reliability. I don't recall many instances
> when a steam excursion caused traffic delay due to
> a steam locomotive issue, but the question is
> could the front and rear engines be considered a
> redundancy for the sake of reliability, being able
> to bring in a train with just one engine if the
> other breaks and avoiding the diesel altogether?

NO!

Big Boy's are simple articulateds, so in theory, you could only drive one set of cylinders, but it would require hughe modifications and I suspect that would cause other problems for the unpowered set. As for the redundancy, I guess the diesel is there to shove the steamer out of the way and get rest of the train down the line. With a few exceptions, if anything breaks on a steamer, it is not going anywhere until it is fixed. The diesel also supplies dynamic breaking and extra power if needed.

Scott Schifer
Torrance, CA
TinyTrains Website



Edited 1 time(s). Last edit at 11/23/13 11:56 by tinytrains.

tinytrains Wrote:
-------------------------------------------------------
> Big Boy's are simple articulateds, so in theory,
> you could only drive one set of cylinders, but it
> would require hughe modifications and I suspect
> that would cause other problems for the unpowered
> set. As for the redundancy, I guess the diesel is
> there to shove the steamer out of the way and get
> rest of the train down the line. With a few
> exceptions, if anything breaks on a steamer, it is
> not going anywhere until it is fixed. The diesel
> also supplies dynamic breaking and extra power if
> needed.

Exactly how would it be possible to "shut off" power
to one or the other engine set?

I'll save you the trouble: It isn't possible.

Well, all I know is that 3985 has run on three cylinders on a Gulf Coast Chapter excursion from College Station to Houston. If on three, why not two?

Focalplane Wrote:
-------------------------------------------------------
> Well, all I know is that 3985 has run on three
> cylinders on a Gulf Coast Chapter excursion from
> College Station to Houston. If on three, why not
> two?

So,,,,,just how & why was the steam supply "shut off" to ONLY one of the four cylinder assemblies?

These questions maka mina beana acha !!! I know the next one coming is: ' Will UP rebuild all the traction motors on the 4014 or are they okie dokie? '

dcfbalcoS1 Wrote:
-------------------------------------------------------
> These questions maka mina beana acha !!! I know
> the next one coming is: ' Will UP rebuild all the
> traction motors on the 4014 or are they okie
> dokie? '


Right after they rebuild the inverters and warp core.

Focalplane Wrote:
-------------------------------------------------------
> Well, all I know is that 3985 has run on three
> cylinders on a Gulf Coast Chapter excursion from
> College Station to Houston. If on three, why not
> two?


The ONLY way you could run the 3985 on three cylinders would be to discombobulate the valve gear on the offending cylinder (remove the eccentric rod and the union link/combination lever? Or, cut the piston stem with a torch?) and block the piston valve in the centered position.

You can do a lot with a torch. Unfortunately, it's usually difficult to undo.

This is the first I've ever heard of this engine being run on 3 cylinders.

-LD

Focalplane Wrote:
-------------------------------------------------------
> Well, all I know is that 3985 has run on three
> cylinders on a Gulf Coast Chapter excursion from
> College Station to Houston. If on three, why not
> two?

When was this? Any pictures? Because it's just not practical.

LarryDoyle Wrote:
-------------------------------------------------------
> Focalplane Wrote:
> --------------------------------------------------
> -----
> > Well, all I know is that 3985 has run on three
> > cylinders on a Gulf Coast Chapter excursion
> from
> > College Station to Houston. If on three, why
> not
> > two?
>
>
> The ONLY way you could run the 3985 on three
> cylinders would be to discombobulate the valve
> gear on the offending cylinder (remove the
> eccentric rod and the union link/combination
> lever? Or, cut the piston stem with a torch?) and
> block the piston valve in the centered position.
>
> You can do a lot with a torch. Unfortunately,
> it's usually difficult to undo.
>
> This is the first I've ever heard of this engine
> being run on 3 cylinders.
>
> -LD

Kinda sorta, Larry.

You can disconnect the valve stem, block the valve on
center, and limp her home. No rods need to be removed.
Or torched.

Assuming the valves are set correctly, no steam will
get by the centered valve to that cylinder.

This is a remedy for getting a locomotive to the
nearest shop in case of a road failure. Nobody
is goofy enough to try to operate this way past a
location where proper repairs can be made.

At least, I hope not.

One addition/correction:

Re: rods to be removed & valves centered...

On radial valve gears:
It would be best to remove the 'union' link and to secure (forward) the bottom end of the combination lever.
There are three pivots in the union link.

Remember that the combination lever moves the valve as the main piston moves, end-to-end, irrespective of the influence of the eccentrics and the swinging link. With the eccentric-rod centered in the Walschaert link, the eccentric motion transmitted to the valve crosshead is virtually zero; so to compensate for a 'lapped valve' and to open the valves (at the ends of the piston's movement, the combination (lap & lead) lever opens the valve admission ports by the amount of 'lead' incorporated by the designers. This occurs with every stroke of the piston.

Thus, (with the above immobilization suggestion) the middle of the three pins (the one in the valve's crosshead) of the combination lever now becomes a locked fulcrum: as the main crosshead completes its strokes, somethings gonna get ruined!
Also, don't forget that the radius rod (from the swinging link) is 'centered' meaning that the valve's crosshead cannot slide; and, it is bolted in the middle of its stroke.

With the lower end of the combination lever swinging back-and-forth, what happens to the connection at the valve's crosshead?
One thing's for sure: it cannot remain stationary. And it ain't gonna be pretty!

Wes Camp.

Focalplane Wrote:
-------------------------------------------------------
> Well, all I know is that 3985 has run on three
> cylinders on a Gulf Coast Chapter excursion from
> College Station to Houston. If on three, why not
> two?


Actually the true story was that while turning at Bryan Junction a castle keeper nut came off the link for the eccentric and so in essence that cylinder was not exhausting in synch like it was supposed to and thus making the locomotive a little lame and sounding sad to us in the cab. But while loading guests at College Station for the return trip the UP Steam mechanical boys worked another of their miracle moves and fixed up a standard nut to use to get us to Houston. Then the next day was a layover day and a gentleman with a machine shop in Houston made us a replacement castle nut. The rest of the trip ran normally. Note there was no delay to the passengers that trip.

Bob Krieger
Cheyenne, WY

CORRECTION....(to note about the valve crosshead, etc...)

WRONG: "There are three pivot points in the union link."

Should be: "There are three pivot points in the combination lever".


Sorry for the typo...

Wes Camp

Bob3985 Wrote:
-------------------------------------------------------
> Focalplane Wrote:
> --------------------------------------------------
> -----
> > Well, all I know is that 3985 has run on three
> > cylinders on a Gulf Coast Chapter excursion
> from
> > College Station to Houston. If on three, why
> not
> > two?
>
>
> Actually the true story was that while turning at
> Bryan Junction a castle keeper nut came off the
> link for the eccentric and so in essence that
> cylinder was not exhausting in synch like it was
> supposed to and thus making the locomotive a
> little lame and sounding sad to us in the cab. But
> while loading guests at College Station for the
> return trip the UP Steam mechanical boys worked
> another of their miracle moves and fixed up a
> standard nut to use to get us to Houston. Then the
> next day was a layover day and a gentleman with a
> machine shop in Houston made us a replacement
> castle nut. The rest of the trip ran normally.
> Note there was no delay to the passengers that
> trip.

Thank you, Bob, for the details, I was hoping you would be able to explain exactly what we the passengers had been told. I was sitting in the Harriman Dome on this journey and the speedometer showed 62mph running down into Houston. I remember the overnight repair being made possible by a local company and the following morning I reported for duty behind the bar in the San Francisco car on a run to Bay City and back. A good weekend!

Rumors, gossip, hate and discontent. Another fun day on Trainorders. ;)

the following morning I reported for duty behind the bar in the San
> Francisco car on a run to Bay City and back. A good weekend!


Boy. there were some stories on the head end on that trip to Bay City and back. We sure teased the heck out of one of our maintenance men

Bob Krieger
Cheyenne, WY

Bob3985 Wrote:
-------------------------------------------------------
> the following morning I reported for duty behind
> the bar in the San
> > Francisco car on a run to Bay City and back. A
> good weekend!
>
>
> Boy. there were some stories on the head end on
> that trip to Bay City and back. We sure teased the
> heck out of one of our maintenance men

And I will admit to something I have kept a secret for years. When we arrived at the counter in the San Francisco the only coffee we had was decaf. What to do? Well, Sunday morning in Houston is not the best time to go shopping for coffee, so we struck a deal. All the coffee we had was coffee. Needless to say, everyone wanted "leaded" so we kept quite and poured out the only coffee in stock. Strangely no-one complained! They even came back for more.

Well we described the alligators that were in the waters around the Wye track where we were scheduled to turn, which had one of our really skiddish mechanical men scared enough to climb over the water cars between the locomotive and the tool car to get there to service the rods.

Bob Krieger
Cheyenne, WY

Almost as big a the Challenger! Well, about 14 feet long. Taken not far from Bay City in the 1990s. I was safely inside my Jeep at the time, they can move fast!

---