This is your forum! With operating steam engines so rare for decades, several generations have grown up with little or no exposure to them. We get asked a LOT of questions about the 1522 and we enjoy educating everyone about the locomotive. On this page, we will list many of the questions we receive with their answers.
First, we have the enclosed chart which answers many of the detail questions asked by serious railroad enthusiasts. It is also a good place for newcomers to get a basic overview of the engine. Make sure you check out the size of the main driving wheels - and the weights involved! 1522 is a heavy machine! Click on the graphic below to enlarge.
How fast will 1522 go?
1522 is capable of doing 90 mph. Since her restoration, we normally run at track speed which is usually around 60 mph. However, we were on a stretch of 79 mph track near Lincoln, Nebraska, in 1995 and 1522 was able to do that speed. That was an exciting trip!
How much can 1522 pull?
So far, 1522's greatest post-restoration challenge was pulling 22 loaded passenger cars up Rolla Hill during the 1990 NRHS Annual Convention. The grade on Rolla Hill is 1.2% with some steeper stretches of up to 1.8% (1.8 feet climbed for every 100 feet traveled).
How much horsepower does 1522 put out?
Locomotives are not usually rated in horsepower but rather in tractive effort - how many pounds of pull they can exert to move the train behind them. 1522 can pull with 56,800 pounds of effort. This equates to roughly 3600 horsepower. Early diesel locomotives which replaced steam engines were in the 1500 horsepower range, so several diesels were necessary to replace a steam engine on a given train.
How does the 1522 work?
Let's compare the 1522 to the engine in your automobile. Your car's engine takes in air, mixes fuel with it, compresses it and burns it to produce energy. This energy moves the car's pistons which are connected by rods to the crankshaft. The piston movement turns the crankshaft which makes the auto move. The auto's engine is known as an internal combustion engine - that is, the burning of the fuel takes place inside the cylinders.
The 1522 has a lot in common with the auto engine, but it is an external combustion engine. Think of it as two separate units - a locomotive with a boiler sitting atop. Fuel and air are burned in the 1522's boiler to convert water to steam. This steam then becomes the propellant - opening the throttle sends the steam down to the locomotive. Here, the similarity with the automobile engine begins again. The auto engine uses valves to control the fuel/air going into the cylinder and 1522 uses valves to control the steam in a similar manner. The steam pushes the 1522's pistons just like the burning fuel/air push the auto's pistons - but the 1522 has steam pushing alternately on both sides of its pistons. The pistons of both engines move rods which, in the case of the 1522, turn the drive wheels rather than a crankshaft. Both engines use a mechanical feedback to control the operation of the valves - the auto via a camshaft and lifters while the 1522 uses various linkages, in a Walschaert's valve gear arrangement, driven by the eccentric arm on #2 driver.
How does this Walschaert's valve gear work and how does it make the 1522 go forwards or backwards?
Rather than trying to explain it here, we have a link to a neat web site provided by Robert Booty where he actually shows how a Walschaert's valve gear works using animated GIFs. Click anywhere on these words to check it out - and be sure to look at the large GIF he has which shows how the linkages are arranged to go forwards and backwards.
What kind of fuel does 1522 burn?
#6 oil - also referred to as Bunker C. To atomize (see next question) properly, the fuel must be kept hot, so steam pipes are routed through the fuel tank in the tender to keep it at 130 degrees F. 1522 did not always burn oil - she was originally built as a coal burner but only stayed that way for a year before being converted. Wood, while burned on real old steam locomotives, does not put out the heat needed to operate larger locomotives like the 1522. On average, 1522 burns 14 gallons of fuel per mile. The tender holds 4500 gallons of fuel oil - enough for 250 miles of steaming.
What do you mean by atomizing the fuel?
Fuel oil is difficult to work with because of its viscosity. While it will burn in its natural state, it will not burn rapidly. If oil was just pumped out of the burner and lit, we would shortly have a big puddle of burning oil in the bottom of the firebox and not much heat to show for it. The fuel has to be broken up, or atomized, to burn quickly. This is done with a jet of steam. As the fuel is pumped out of the burner, it immediately falls onto this jet of steam which breaks it up for better burning. Operating the atomizer is a major chore for the fireman along with controlling the flow of fuel, the boiler water level, calling signals, etc.
Why does 1522 make a 'chugging' noise when it operates, especially when just starting up?
While the noise comes from the smoke stack, the reason behind it starts back at the firebox. Large quantities of fuel have to be burned to generate the heat needed to boil the water. If no outside draft were present, the fire would starve for lack of oxygen. So, a draft is created by ejecting the used exhaust steam from the cylinders up the smokestack. As the steam expands up the stack, it creates a vacuum as well as making that 'chugging' noise. This vacuum pulls the exhaust gasses from the firebox through the boiler flue pipes up to the smoke box and out the stack, which creates a draft inside the firebox to draw in more outside air.
Now, to REALLY complicate the issue, you will notice that the 1522 is REAL loud when first starting up. That is because the locomotive is using full boiler pressure to start up - essentially a straight pipe from the boiler to the cylinder. Comparatively little steam expansion takes place before the valve closes the cylinder and the piston reaches the end of its travel. When this steam is exhausted out the stack, it does a LOT of expansion and makes a lot of noise. Once the 1522 is moving along, less steam is needed and the engineer moves the reverse system to only put a 'shot' of steam into the cylinder - relying much more on the expansion of the steam to provide the power needed. Thus, when this 'shot' of steam is exhausted out of the cylinder, it has a lot less energy and is much quieter. 1522 is one of the loudest locomotives operating today. We are quite proud of that!
What does the 1522 do for a draft for the fire when standing still?
A ring of jets is opened to shoot steam up the smokestack and create the draft. For startup, an air compressor is connected to these jets until sufficient steam pressure is available.
What is a superheater and does 1522 have one?
A superheater is a device used to increase the power of steam locomotives. Locomotives boil water to make steam, but once out of the boiler, the steam wants to condense back to water. Since the temperature of the water and steam are relatively close to the point at which it boiled, this condensation is a very real problem. As this 'saturated' steam expands in the cylinder, it will condense and limit the amount of power the locomotive can produce. Superheaters were invented to raise the temperature of the steam to prevent the condensation and to give the steam more energy. The superheater is a unit downstream of the throttle. As the throttle opens and steam comes out of the boiler, the superheater routes it through pipes which thread back through the boiler flue pipes. The hot exhaust gasses in the flue pipes transfer even more heat to this steam and raise its temperature even higher - giving it extra energy and preventing condensation. The 1522 has a Type A superheater.
What is a feedwater heater and does 1522 have one?
In the normal course of operation, a lot of heat energy goes up and out of the smoke stack (steam engines are not very efficient). If some of this heat could be transferred to the water being added to the boiler, it would reduce the amount of fuel needed to bring this additional water to boil. Feedwater heaters take the steam exhausting out of the cylinders and transfer some of this heat to the water going to the boiler, or feedwater, to raise its temperature. 1522 does not have a feedwater heater.
Stationary boilers and ship boilers condense their steam back to water and re-use it. Why don't steam locomotives do that?
Some did - most notably, locomotives being operated in desert climates. However, these condenser units did not work very well. They work well in ships and stationary boilers because large cooling ponds or bodies are available to cool this steam back to water quickly. The equipment also takes up a lot of space - which is not available on a steam locomotive. 1522 never had any such device.
The statistics chart says your boiler operates at 210 psi. At that pressure, how do you force in the water to replace the steam being removed from the boiler?
To overcome the boiler pressure, a steam powered injector forces the feedwater through a check valve and into the boiler.
When 1522 is just starting up, steam shoots out to the sides under the cylinders. What's with that?
When first starting out, 1522's cylinders are relatively cold. In addition, some steam may have leaked in and cooled back into water and some crud might have found its way into the cylinder. The cold cylinder will cause the steam to condense back into water. If this water is not removed, enough of it could build up to damage the cylinder and piston in a hydraulic lock. To prevent this, the engineer opens the cylinder cocks under the cylinder to shoot some steam, and the water/crud with it, out of the bottom of the cylinder. You will note how first one end of the cylinder and then the other will have steam exhausting as the piston moves back and forth. After a few revolutions, the cylinder wall is sufficiently warmed and the accumulated water is cleared, so the engineer shuts off the cylinder cocks. If the engine has only been sitting a short time, the engineer will often not bother with the cylinder cocks. Every so often while the engine is at speed, the engineer will briefly open the cylinder cocks to clear the cylinders out.
I was trackside watching 1522 approach me at a distance when I saw this huge stream of steam shoot out of the left (fireman's) side of the engine. What was that all about?
The boiler on the 1522 is designed to evaporate a lot of water as quickly as possible (100 gallons per mile!). As you know, water contains minerals and impurities. When the water evaporates into steam, these impurities and minerals fall to the bottom of the boiler where, if left alone, they will accumulate at a rapid rate. This accumulation is especially troublesome in the area surrounding the base of the firebox - an area called the mud ring for this very reason. To prevent this 'mud' buildup, several blowdowns are installed on the engine. These blowdowns open certain parts of the boiler to atmosphere and the escaping steam carries out much of the deposited minerals. The one you saw is the most dramatic - the fireman's blowdown. The fireman will open this up in several shots of 3 seconds each to flush out the minerals. The engineer also has a manually operated blowdown but its steam escapes straight up and is not readily visible. There are also 'continuous' blowdowns which continually remove mud from the boiler. Blowing down the boiler, along with water treatment enroute and flushing and washing out the boiler, help keep the 1522's boiler free of scale.
Speaking of water, why the water car and tender. Isn't 1522's tender big enough to supply its needs?
Originally, the tender on the 1522 was adequate for its water needs. The tender holds 11,700 gallons of water (and the boiler holds another 4000 gallons). At an average consumption of 100 gallons of water per mile, the tender holds enough water for 110 miles or so of steaming. However, you never want to run out of water, so including reserves, the 1522 can operate for roughly 90 miles before needing water. On the Frisco in the days of steam, this was not a problem as they would have water towers spaced every 50 miles or so and the engines would make several stops along the way for more water. On modern railroads, the water towers are long gone and taking water is now done through fire hydrants, a much slower source than the tower's fill pipes. Since we want to minimize our disruptions to railroad operations, we don't want to keep stopping for water every 50 miles, so more water capacity was needed. At first we used an old tank car as a water source, but then we found an old auxiliary water car built for this very purpose and it now adds 13,000 extra gallons of water. This allows us to run without worrying about water for 125 miles or more - at which point we have to stop anyway to service the locomotive.
Tell us about the servicing of the locomotive on a trip. You pull in and stop and soon there are a bunch of guys working on the engine. What are they doing?
A steam locomotive is a machine - in this case, one that converts fuel energy into mechanical motion via steam. Like any machine, the 1522 must be kept properly lubricated to function correctly. Every 125 miles, the engine is stopped and the service crew appears to do their work. The running gear of the locomotive is greased, fluid topped off and water replenished. In some cases a tanker will meet the engine at the service stop and fuel will be added. The goal is to be completely watered and serviced and back underway within an hour.
A pair of crewman go around the engine pumping something out of a big 5 gallon can - what are they doing?
They are pumping red grease into the various button grease fittings on the running gear. This is the same grease you would use to grease up the suspension components on your automobile. Another crewman is usually out there with a similar pump can shooting a higher pressure grease into the drivers to lubricate the driver side (hub) bearings.
Another pair of guys go around with some sort of air driven contraption that makes lots of noise. What are they doing with it?
They are shooting a stick grease into the bearings on the drive rods. Because of the forces exerted on these bearings, regular greases would not provide adequate lubrication. A stick grease is used instead. It comes in a large block and we use a press to extrude this grease into a hot dog shaped stick which is then rolled in graphite. Because of its consistency, an air driven gun must be used to shoot the grease into the bearings. The crewmen connect the gun to the 1522's air reservoir and use this pressure to shoot the grease.
What are some of the other lubricants that must be inspected?
The 1522's air compressor uses both steam oil and air oil - oils which are formulated to retain their lubrication properties when exposed to their respective materials. The dynamo supplying electric power to the 1522 also has an oil sump that must be checked. The two lubricators, one on either side of the engine, use a drive arm from the locomotive's valve gear to create a pumping motion to force steam oil to various bearings on the drive train as well as lubricating the piston and valves in their cylinders. A lubricant that was just eliminated was the journal oil in the wheel bearings under the tender. These bearings were replaced with roller bearings which require no lubrication in the field.
Are all these lubrication requirements new or did 1522 receive such lubrication when in regular operation?
All of these lubrication requirements existed when 1522 was in regular service. Steam locomotives of her vintage would only run 120 miles or so before needing service. Railroads differed in their maintenance philosophy - some would have a service crew meet the engine at 120 mile intervals and service the engine at a stop while other railroads would pull the engine off the train at that point and replace it with a freshly serviced engine. The Frisco usually lubricated at waypoints and sent the engine on its way. Some of the newest steam locomotives have the advantage of roller bearings on their moving parts, which dramatically reduce the lubrication requirements. We aren't that lucky, so frequent, thorough lubrication of the 1522 is one way to assure proper operation.
When was the 1522 built and what did it cost?
It was delivered from the Baldwin Locomotive Works in Philadelphia in May, 1926. The delivery invoice lists the cost at $69,736.
Why is it called the Frisco 1522?
The 1522 was purchased by the St. Louis-San Francisco Railway. This railroad was known informally as the FRISCO Railway. Ironically, it never operated anywhere near San Francisco.
Normally, when a railroad starts buying a new class of locomotive, they will assign a series of numbers for that class. The Frisco started buying Mountain type locomotives and assigned them the 1500 series of numbers. The first Mountain they received became the 1500. The 1522 was the 23rd Mountain class locomotive received out of the 30 that were purchased.
Why is the 1522 called a Mountain?
The type designation of Mountain has nothing to do with where the engine was operated. It is a name given to a specific wheel arrangement. The 1522 has a 4 wheel pilot truck (under the cylinders), 8 drive wheels and a 2 wheel trailing truck under the boiler and cab. This 4-8-2 wheel arrangement became known as a Mountain wheel arrangement. Engines with one less drive axle would be 4-6-2 locomotives which are known as Pacifics.
You mention the pilot truck and trailing truck - what are these for? Why wouldn't you put all the weight on the drive wheels?
There are many reasons for this and locomotive design is far too complicated to be discussed in depth here. The 4 wheel pilot truck in front supports some of the boiler and locomotive weight, but its main function is to guide the front of the locomotive through curves at high speeds. The trailing truck is used because of the firebox. If you look at photos of real old locomotives, you will see that their drivers were back under the cab and the firebox was between them. As fireboxes became larger to get more grate or burner area, they had to be moved behind the drivers to allow them to be expanded to the full width of the locomotive. This puts a lot of weight behind the drivers - so the trailing truck is positioned under the firebox and cab to carry some of this weight. Steam switch engines generally did not have pilot or trailing trucks as they were not going fast enough to need to be steered through curves nor were they long enough to have balance problems from firebox placement. Also, given the slow speeds and heavy loads they moved, it was desirable to put all their weight on the drivers.
NEW What are the tanks atop the boiler? I have seen photos of other Frisco 1500 series Mountains that did not have those.
Those tanks are the main air reservoirs for the locomotive's air system. There are two tanks and, in between, a series of pipes that help cool the air that has been pumped into the tanks. Not all Frisco 1500 series had their air tanks atop the boiler. The ones that did were delivered from the factory with a steam injector. As can be seen by the photo of the 1516, the piping for these injectors took up a lot of space under the fireman's side running boards where the air tanks would normally reside. So, the tanks were moved up on top of the boiler. Later, the injectors were replaced with the Chicago T-80 injectors we now have and that large piping removed. However, the tanks were not relocated and that's why the 1522 has them where they are.
NEW How is the 1522's tender attached to the engine?
The tender is connected with a pair of drawbars - one main drawbar and another that is backup bar for safety. The bars are connected to the locomotive and tender using large pins (roughly 6 inches in diameter, solid steel).
When you go on the road, who operates the engine?
Association members fire and operate the locomotive. These crewmen must meet the same standards and pass the same tests as professional railroaders. We also take aboard a pilot crew from the railroad - a regular train crew that knows the line we will be running and can advise our engineer about the unique characteristics of that route.
How do you get permission to use the tracks you operate on?
This is one of the most vexing issues of operating a steam locomotive on the contemporary rail system. Unlike other modes of transportation, the tracks in this country are privately owned. The railroads exist to make a profit hauling freight on their tracks. Steam locomotive operations for excursions or display are not profitable - actually quite the opposite. They are disruptive to normal operations. Because of this, and insurance considerations, many railroads do not allow any steam locomotives on their tracks at all - they do not wish to be bothered. As much as we might wish otherwise, we have to deal with this situation and do our best to work around it. Union Pacific has their own steam program and understandably is not interested in letting anyone else run on their system. The SLSTA has been very fortunate over the years to have a good relationship with the Burlington Northern, and subsequently, the Burlington Northern Santa Fe (BNSF) Railway, which has allowed us to use their tracks. Even then, the BNSF won't allow just any move - it must be in conjunction with some special event.
Why are steam operations disruptive? You are running the same speed as everything else out there.
Speed is important, but modern freights run straight through between terminals while steam trains end up stopping for servicing and display. The steam trains also draw crowds to the tracks - and the railroad usually assigns several of their special agents (police) to escort the train and deal with safety issues. The trick is to do everything possible to get the engine out, get over the road as quickly as possible and then get out of the way. This keeps railroad disruptions to a minimum and improves our chances for future operations.
We're having a big festival in our town next month and it would be wonderful to have 1522 join us. Can you bring her over?
Well, this is very short notice - steam trips usually take months, if not a full year, of planning. First, does your town even have any track that could be used? Does the railroad that owns this track allow steam train operations? Will the track support the steam engine - issues such as curvature and bridge strength have to be looked at. How much insurance would be required and can it be obtained at a reasonable price? Can the sponsoring group afford the costs of bringing 1522 to the fair? At a budgeting cost of $25 a mile plus other costs, moving the 1522 anywhere gets costly very quickly.
When you go somewhere with the engine, do you do any preliminary work scouting the route?
Yes! Since the whole idea is to minimize disruption, we don't want to just set out on a trip without detailed plans on where we will stop and what we will do when we make these stops. One or more crewmen will scout the route to be taken and determine good places to stop as well as fire hydrant locations.
When was the Association founded and for what purpose?
The Association was founded in 1985 with the goal of restoring a steam engine for main line operation.
Is the SLSTA a for-profit operation?
No, it is a 501 (c) 3 not-for-profit, charitable organization. All contributions are tax deductible.
How many members does the Association have?
Roughly 100 - of which 25-30 are regularly active.
Are all of you professional railroaders?
No, we have quite a varied number of professions but share a common interest in preserving and operating the 1522.
Does the SLSTA operate excursions?
No, SLSTA operates the 1522. We leave the excursion business to others and provide the motive power.
This page will be a continually evolving listing of the questions asked of the crew on the road and of the web site. If you have a question not already asked, drop us a line at:
and we'll add it to this page!