Run out of steam pressure after 100 feet

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Bill Shields
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Re: Run out of steam pressure after 100 feet

Post by Bill Shields »

note:

i know it is tempting to just put your finger over the hole.

doing so is a very dangerous practice...granted there is little chance of blowing air into a vein on your thumb and getting bubble back to your heart / brain...but if you don't do it at all...there is even less chance...so why take the risk.

that is why God made pointy sticks.

if you don't have a pointy stick and want to cover the hole with a piece of rubber and push on the rubber with a rounded broom stick...you can see where this is headed...

after you make the stick..keep it around.

There are times when you are 'blowing things out' - rare on propane but...and you don't want to blow stuff down into the stack so that when you are 'pushing around' they get sucked INTO the cylinders / valves because you have the valve gear in forward and are pushing in reverse...everything in the exhaust passages gets sucked INTO the mechanism and can raise havoc.
Too many things going on to bother listing them.
ERIE S-1 BERKSHIRES
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Re: Run out of steam pressure after 100 feet

Post by ERIE S-1 BERKSHIRES »

I watched the video the engine has the blower on you're running propane, you don't need a blower to pull draft through the boiler ! only crack it just a little bit ,second when I heard that your fire has propane and running out of steam I thought of my friend he's got the same engine same problem the burner is not correctly sized to the engine most likely too small, previously before engine was fired on coal locomotive did not run out of steam, this noise you heard coming out of the stack was the blower on full volume when it's that high up you're pulling all the heat out of the boiler causing you to run out of steam
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Drprez
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Re: Run out of steam pressure after 100 feet

Post by Drprez »

No the noise is not the blower I turn the blower off and that is what I get. I am looking at the valves so I will know more today thanks
Nicholas Kalair
Las Vegas, NV

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LVRR2095
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Re: Run out of steam pressure after 100 feet

Post by LVRR2095 »

Another point to consider is how long have you waited after reaching operating pressure until you start your run. Just because you are up to pressure you are NOT ready to run. If the locomotive is still cold to the touch....every bit of that cold metal is pulling heat out of your boiler. On small locomotives this is very important. After reaching your running pressure you have to wait until ALL of the locomotive is at least warm to the touch. This means the drivers, the frames, everything. One my small locomotives I take a break once steam is up. Have a sandwich, hit the bathroom, or chat with family and friend. You want the engine to approach thermal equilibrium. When you think you are ready to go....it is time to warm up the cylinders. Open the cylinder drains and just crack the throttle with the valve gear in forward. Let steam escape from the cylinder drains. Then move the reverser to reverse and again crack the throttle just enough to let steam and water escape. Do this again until only dry steam comes out of the drains and the cylinder castings are warm.
Now you are ready to try a run.
The best advice you have gotten so far is to get together with folks that have done this before. And remember that smaller locomotives are not as forgiving as the big ones!
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ALCOSTEAM
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Re: Run out of steam pressure after 100 feet

Post by ALCOSTEAM »

It sounds like the timing could use some work and if the video of it where the smoke is going back into the stack is of it actually in reverse it sounds really off in timing. Stephenson valve gear should be capable of being timed to run the same in forward as in reverse.
You need to ensure your water level is where you think it is. If you only have an inch or two of steam space above your water level you will run out of steam quickly.
The video of the engine running forwards, there isn't a speck of steam visible anywhere, even the best of engines seem to whisp steam from somewhere. Most engines are hot enough that water coming out of the stack will hit the jacket and turn to steam.
Glenn Brooks
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Re: Run out of steam pressure after 100 feet

Post by Glenn Brooks »

Alcosteam, those were my thoughts also. I think Nicholas might be in Nevada. So, Could be 80 or 90* F there when he shot the video. If so, he wouldn’t get so much visible condensation as where he running in a colder climate. But, the steam has to go someplace! Looking forward to more info concerning what’s happening...

Glenn
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NWCF_1
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Re: Run out of steam pressure after 100 feet

Post by NWCF_1 »

New to you steam locomotive? Have you had a look inside the boiler? A little difficult to assess internal condition while looking on the outside. Valve timing is off. It would also be better to have a chance at evaluating if your second running video wasn't running backward.
At this point there are LOTS of unanswered questions. i would at least want to take it to a local club for an inspection/evaluation and some good advice.

Cheers!

Stan
Garage cleaning as complete as possible- next step test Lincoln Idealarc 250 roundtop
RET
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Re: Run out of steam pressure after 100 feet

Post by RET »

Hi,

Here is something you can try fairly easily. Pull the front off the smokebox. Move the Johnson bar to either full forward or full reverse. Roll the engine or turn the drivers until on one side the valve rod on the valve chest is either all the way out or all the way in. Stick a couple of rods through the spokes so the wheels can't turn. Make sure the throttle is closed and the blower is off. Pressurize the boiler with air to somewhere between ten and twenty pounds (you don't need any more than that). Get a piece of soft flexible tubing (either plastic or rubber). Stick one end in your ear and with the throttle cracked open move the other end around in the smokebox to see where the air leaks are. Check all the smokebox piping. If air is leaking anywhere other than the blast pipe, fix those leaks. At this time, also use the hose to check both the valve chest and the piston rod glands for leaks.

Now, if everything is set right, there should be little or no air coming from the blast pipe. If there is quite a bit, then either air is blowing by the piston rings or the valve isn't set right. If the valve moves too far, you can get a direct connection between the steam chest and the exhaust. To check on this, move the Johnson bar towards mid-gear and see if the air noise changes.

Repeat this with the valve rod on the same steam chest at the opposite extreme travel position and see what results you get. Once this has been done, do the same with the steam chest on the other side of the locomotive.

Using this method, you should have a fair idea where the problems are and what needs to be done to fix them.

Unless it primes, the amount of steam space above the water in the boiler isn't really a factor because there is a lot more stored energy in the water in the boiler to flash water into steam as required. The engine runs, so things can't be REALLY off. As much as is practical, try and limit the amount of excess air that flows by the burner because that can have a marked cooling effect. With propane, the flame should be blue with little flecks of yellow. If the flame is yellow, there isn't enough combustion air, if it is all blue with no flecks you may have more air than is necessary. Either extreme will result in a lower flame temperature.

Perhaps this will help a bit. Taking it to someone with experience is still very good advice.

Richard Trounce.
Pat Fahey
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Re: Run out of steam pressure after 100 feet

Post by Pat Fahey »

Hi Drprez
They are a lot of people good people trying to give you the best advice, without really seeing just how the locomotive performs, sort of sight unseen, the video does help. As one of the posts did suggest, that you get in contact with your loco steam club, for some advice.
What I would like to know, because it is hard to see, from the photos, Does the locomotive have superheaters in the boiler? If so it could be possible that the superheaters are leaking, and the Steam is not getting to the cylinders but going right up the stack.
Next, what do you have for water supply, I saw a steam pump mounted on the left side of the boiler, do you have an injector or an axle pump, also. The reason why I am asking, IF you have an axle pump, it could be pumping water into the boiler, and draining the steam?? If the axle pump has a by-pass, turn it to the on position so it pumps water back into the tender or on the ground.
The Steam delivery pipes, in the smokebox, could be leaking, coming off the dry-pipe? Also, the smokebox could be sucking air. Another reason why you could be losing Steam, the exhaust nozzle, could be out of alinement, to the petticoat pipe, in the smokebox. Well, I hope some of this information helps, Pat Waushakum Live Steamers.
Vance Nickerson
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Re: Run out of steam pressure after 100 feet

Post by Vance Nickerson »

If your firebox looks like this give up and get a new boiler. My third boiler this year with the same problem. Wouldn't maintain steam and passed the hydro test. Look inside the blow down holes or steam dome and I'll guess it's never had a boiler wash. When a customer says they run out of steam fast this is usually the reason.

Vance Nickerson
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NWCF_1
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Re: Run out of steam pressure after 100 feet

Post by NWCF_1 »

^^^^^

What he said!
I would never buy a locomotive and fire it up without a full (get inside, RVI-type look) before I went on to a pressure test.
Without knowing previous maintenance, whether or not it was stored properly, or whatever reason one could imagine (such as temps well below freezing). Seems to be a big risk to pressurize without knowing what you have.
Perhaps the boiler is full of scale and mud-reducing the volume for storing steam. 100' isn't very far for 100PSI worth of steam on level track.
Get some help, remove plugs (not while under any pressure!) and have a look. Good luck with your findings.

Cheers!

Stan
Garage cleaning as complete as possible- next step test Lincoln Idealarc 250 roundtop
Kimball McGinley
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Re: Run out of steam pressure after 100 feet

Post by Kimball McGinley »

All of this is great advice; but I have an issue with one item that was said a few times. It was said that "...too much water is no good because there is less space for steam..." but that does not make sense. Steam is readily formed from the hot water when the existing steam is drawn off. Fireless locomotives were basically all but filled with hot water and worked that way until almost empty.

The main reason to not have the boiler almost totally full is to avoid sending water to the cylinders instead of steam; that is why there is a steam dome.

Some steam space is also desirable to maintain some compressible space, for example, when pumping in make-up water. You don't want the boiler to "go solid" with water, like we do in a Hydrotest, since the pressure could skyrocket.....
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