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Need some help diagnosing a Frank S live steamer... not sure where to start.

Bought the locomotive used. It has had the collection tank removed, but other than that is stock.

I've noticed that when running it, it has trouble keeping steam pressure up. It lights up fine and the burner seems to be working correctly. By the gauge it gets to 3 bar within about 10-15 minutes. Once the pressure is up enough that the relief valve opens, it heads off happily.

However, with the gas almost full on and the throttle just cracked, it will run for about 8 minutes before the steam pressure has dropped to where it's not sufficient to drive the loco. If I close the throttle and wait a couple minutes, the pressure goes high enough for it to run a similar amount of time. But then again in about 8-10 minutes the pressure has dropped to where it won't drive. I can repeat this process two or three times per run.

I'm such a steam novice that I'm not sure how to even start figuring this out, so any advice would be most welcome.
 

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Hi RD

Are you adding tepid tap water to the tank in the tender around the butane tank? Your problem sounds like the classic issue of the butane chilling as it flows to the burner, thus reducing it's vapor pressure and diminishing the generation of steam. Try adding tap water to the tank and let me know what happens

Jerry
 

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Hi RD

Are you adding tepid tap water to the tank in the tender around the butane tank? Your problem sounds like the classic issue of the butane chilling as it flows to the burner, thus reducing it's vapor pressure and diminishing the generation of steam. Try adding tap water to the tank and let me know what happens

Jerry
Thanks Jerry.

I am putting "room temperature" distilled water into both the boiler and the tender tank.

I've read that it's not advised to put warmer than ambient water into the tender tank... is that true? If not, I could put warm water (not hot) in and see if it helps.

Somewhere I saw a modification someone did where they sent hot water from the boiler (I believe off the throttle, but don't recall for sure) into a copper coil around the tank to help with that problem, but that's probably beyond my soldering/fabricating ability at the moment.
 

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You are correct, putting truly hot water around the butane tank is not a good idea. I have used warm water from the tap as the weather cools and that helps. You might also us a turkey baster to suck the now cold water from around the tank and replace it with warm water when the loco slows down...if it starts working well again, that could be an indicator. however my Frank S seem to get a good long run, as long as I have added water around the butane tank. Yes I have heard of that mod to bring a steam coil back, but I don't seem to need it.
I have found there are pros and cons to butane tank placement. If the tank is near the boiler (Accucraft Forney, eg,) it stays warm and works very well. However, when you want to refill it, since it is warmer then the butane can, it may not want to fill due to it's internal pressure. In our case our Frank S tanks are far from the boiler, and chill with reduced butane flow resulting, but it is easier to add butane to a cool tank....

Of course you might wish to clean the gas nozzle just for grins, but this does not sound like that is an issue.

and BTW if you have not seen this it is the ultimate tutorial on operating Frank S..

http://www.southernsteamtrains.com/notes/franks1.htm

Jerry
 

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Discussion Starter #5
Thanks again Jerry.

I'd seen that before, but lost track of the link. He does mention adding 100 degree water from a thermos if the water in the tender gets too cold. I might try that...
 

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Heater valve modification is not off the throttle, most time it is a take off from an extra plug on the boiler or used of the whistle boiler connection. You can simple route a cooper line of the boiler with the valve directly into the tender.
 

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At one time, a builder offered a replacement gas tank that sat in the fireman's side tank on the locomotive. This cured the Frank S steam generation issues. But alas its no longer available. I to have to deal with water in the tender to keep my Frankie steaming, espicaly in colder weather. I am hoping to find someone to fabricate me a new fuel tank that mounts like the old Finescale Engineering one did. Only 3 holes to drill, one in the tank top to poke the fill valve thru, and 2 for the mounting feet screws. Mike
 

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I have a frank also.
All you need to do is add warmish water to the tank. Like the loco, this is experience. I start almost dry, and trickle warm/hot water as needed. The controls are pretty much on/off for fuel, so, a bit of water increases pressure. Too much hot water over the fuel tank will cause a flame out. A bit willl do it and you can hear whats happening.

I start almost dry and add a bit as needed. A little water acts as a ballast to slow fuel tank cooling.

If convenient, try using hot water , distilled, in the boiler. This speeds up coming to pressure. Especially in cold weather. I use a thermos trackside, for warm water for the tendr tank. You can overfill without issue.

The big issue is that frank carries more fuel tan water, and the sight glass isnt always reliable. Mind that when pressure drops , shut off gas immediately to avoid paint scorch etc. fyi my runs are about 18 minutes, give or take. I have never run to a dry point in the boiler.

Mine was new when i purchased. I might suggest gently tightening ALL screws before each session. Especially cylinder assembly under boiler, and driver wheels . Gently but consistently. Should the driver screws work loose, its a PITA, as they catch the connnecting rod, and you can lose the screw and or tension washer.
 

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I often add fairly hot water to the existing cool water until I hear the gas flowing more vigorously. This has to be repeated and adding properly warm water which is harder to get a good temperature if cool water is in the tank.
 

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I often add fairly hot water to the existing cool water until I hear the gas flowing more vigorously. This has to be repeated and adding properly warm water which is harder to get a good temperature if cool water is in the tank.
I second what Eric is saying and it may have been my post that you referenced earlier. I do not put HOT water into a dry tender, that's bad. At the beginning of the run, I add about 1/4 of a cup of any other water that happens to be around, usually room temperature distilled because it's handy. But only after a few minutes of operation, the water in the tender becomes rather cold and the flame will suffer the symptoms described exactly in your first post.

After the water gets cold, I add hot water from my thermos (as hot as will come from my tap) but only enough to make the water in the tender warm (usually just a tad more than a splash). As Eric said, you will hear the flame vigor increase. It seems as this is necessary for ANY run where the ambient temperature is below 80F.

The ONLY other operational problem that I've ever had was a clogged jet, but with this loco, it is very easy to check:
Disconnect the tender from the engine but leave the fuel line with jet assembly attached. Make sure the fuel tank has gas, then open up the gas valve and invert the tender so liquid fuel squirts out of the jet. A nice solid stream of fuel should shoot directly out of the jet (not at a funky angle) and should shoot out at least a foot (or more) before is dissipates.

Needless to say, do not perform this operation around other engines that my be lit off, as you may discover one of the definitions of the word flambé.

I used to disconnect the fuel line from the tender with that thumb wheel connector, but that does allow dust particles to enter the gas line upstream of the jet and I would be clearing that jet very often. I now just pull the jet holder assembly out of the burner (held in by a sprung ball) and leave the entire assembly attached to the tender. I haven't cleared a clogged jet in years.
 

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I have a frank also.
All you need to do is add warmish water to the tank. Like the loco, this is experience. I start almost dry, and trickle warm/hot water as needed. The controls are pretty much on/off for fuel, so, a bit of water increases pressure. Too much hot water over the fuel tank will cause a flame out. A bit willl do it and you can hear whats happening.

I start almost dry and add a bit as needed. A little water acts as a ballast to slow fuel tank cooling.

If convenient, try using hot water , distilled, in the boiler. This speeds up coming to pressure. Especially in cold weather. I use a thermos trackside, for warm water for the tendr tank. You can overfill without issue.

The big issue is that frank carries more fuel tan water, and the sight glass isnt always reliable. Mind that when pressure drops , shut off gas immediately to avoid paint scorch etc. fyi my runs are about 18 minutes, give or take. I have never run to a dry point in the boiler.

Mine was new when i purchased. I might suggest gently tightening ALL screws before each session. Especially cylinder assembly under boiler, and driver wheels . Gently but consistently. Should the driver screws work loose, its a PITA, as they catch the connnecting rod, and you can lose the screw and or tension washer.
Steve, I would beg to differ on the sight glass on the Frank S. I believe it is probably one of the most reliable sight glasses in this hobby. The giant porthole like window allows you to look into the boiler and at times you can actually see the water boiling!
 

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Frankie defiantly has one of the best site glasses in the small scale steam world, if a bit unsightly in design. Much more accurate than a small tube style that tend to be hard to see. The gas firing issue has been discussed many times since LGB introduced the model Warm water in the tender is the only real easy solution right now. Mike
 

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Well it may be the best, but, it can show /retain lip of water near the base, which can make it appear to be the boiler water level, when in fact, the level is lower.
 
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