# Ruby #5



## Ray Cadd (Dec 30, 2008)

Having had much experience with large scale live steam on up to full size, I'm almost embarrassed to admit that my Ruby #5 has me stumped. The issue is this; it runs, but not terribly well. It's performance is very anemic. I have to fire it hard to maintain a good head of steam. It will pull no more than three or so small cars. Under load, once around the track, pressure has dropped from 40+ to just over ten. What has me a bit suspicious, is there seems to be quite a bit of blow by from the exhaust, almost like a constant, undefined rush of steam. You can hear the exhaust beats, but very faint. 
I've looked at Hotmann's site on reversing admission (which I also did), in order to understand the piston valve events. I did pull the (cylinder) pistons to have a look, and the rings appear to be ok. I'm wondering if the issue is in the reversing block? That bit appears to be adjusted correctly to the hash mark. Looking to trouble shoot this thing.. Any ideas?


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## Phippsburg Eric (Jan 10, 2008)

Is this a new or heavily used engine? have you run it successfully previously? can you run it on compressed air pumped into the boiler? does it run better forward than reverse? 

If this has only happened since you reversed the admission it is likely the timing is off as you would have adjusted that. do the piston valves align with the "mark" when in the forward end of the stroke? 

It sounds to me like the steam is leaking out past the reverse valve. is it worn?


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## Ray Cadd (Dec 30, 2008)

New engine, barely used. On it's own, it will sail around my layout. Did the compressed air deal to run in initially, and during the procedure to reverse admission. Due to that procedure, it runs 'ok' in forward, not as well in reverse, as to be expected. I doubt the timing's off. What exhaust beats I can hear seem to be fairly even, and there's no stalling. 
I'm suspicious of the reverse valve too. It is not worn, but I am thinking there might be a manufacturing defect....not sure if there's a way to test it (?).


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## Semper Vaporo (Jan 2, 2008)

Put the engine in forward or reverse and open the throttle, but hold it down so the wheels won't turn. Is there steam coming out the stack? Hear any hissing of steam escaping someplace. Easy way to find it if you live in a cold climate is to take it outside and look for plumes of steam from anyplace it should not be coming from.... if it is not running there should be none from the stack either. If there is steam from the stack then there is blowby somewhere in the system... Either in the reverser valve or one or both cylinders. Could also be a cracked pipe or joint someplace.


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## HMeinhold (Jan 2, 2008)

An excellent tool to locate leaks is a stethoscope, e.g.
http://www.harborfreight.com/mechan...41966.html 
Use compressed air, steam might be too aggressive for your ears







.
Regards


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## Steve Shyvers (Jan 2, 2008)

Even a length of plastic tubing can be used as a make-shift stethoscope to listen for steam leaks. The end of the hose can be positioned near glands and unions, and can be very effective to isolate sources of leaks. I have used a length of tubing to diagnose piston ring blow-by in a two-cylinder oscillator. I used compressed air at low pressure and turned the engine over by hand. 

I learned also when testing that these small locomotives seem to behave better under compressed air than under steam, even though the air pressure at the compressor is a lot less than the steam pressure in the boiler. I've had steam engines run great on air, even with significant piston blow-by, but then were non-runners on steam. I'm not sure of all the factors why, but believe that one main one is because the compressor can supply a comparatively much greater volume of air into the cylinders, even at low pressures, than the typical little boiler can supply of steam. Also air does not condense in the cylinders and steam does, which can rob it of a significant percentage of its volume. these small locos with little unlagged cylinders have proportionally huge thermal losses compared to larger cylinders on larger locos. (Ratio of surface area to volume.) 

Steve


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## Phippsburg Eric (Jan 10, 2008)

I am not trying to be a pain in the caboose but my experience has found that the adjustment of the valves is trickier than one would hope. 

I would go over the procedure again carefully, step by step see if you can improve it. I have had such issues and was at a loss to explain why it worked, then didn't work then did again. 

One procedure that has been quite useful is to remove the side rod and adjust the valve so that the piston moves (under air pressure) in the desired direction in the correct quadrant of wheel rotation and equally top and bottom of the wheel rotation. 

here is a link to Mr. Hottmann's page http://www.mbv-schug.de/Ruby_-_Adjustment.pdf 

here is another link to a very detailed discription of timing a ruby http://www.ironhorse129.com/Prototype/SteamClass_1/SC_Ch4_26.htm click the next or previous buttons at the bottom as needed.


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## afinegan (Jan 2, 2008)

Not that is hasn't been mentioned, but your running steam oil right lol

An engine not running the proper steam oil will leak steam around its valves and fittings, (not that I do this often), I can tell when my seam engines need steam oil because small leaks develop around the cylinder gasket.

BTW, Dave Hotmman is the ruby expert, after seeing what he brought to diamondhead, wow! (you can hear what a properly timed ruby sounds like anyway)


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## gwscheil (Aug 6, 2008)

The difference between ho-hum and in-the-groove can be startling. I had to replace worn eccentrics and spent hours tweaking timing to get it OK but not great. Then happened to shift one of the eccentric valves a fraction of a turn and she took off. So just aligning with the mark may get it close, but not necessarily perfect.l


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## Ray Cadd (Dec 30, 2008)

Thanks guys for the advise- diagnostic procedures is exactly what I'm looking for here, specific to this engine. Will try the stethescope, and if that doesn't turn up anything decisive, will re-check timing.


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## Ray Cadd (Dec 30, 2008)

Posted By afinegan on 07 Feb 2012 07:46 AM 
Not that is hasn't been mentioned, but your running steam oil right lol

An engine not running the proper steam oil will leak steam around its valves and fittings, (not that I do this often), I can tell when my seam engines need steam oil because small leaks develop around the cylinder gasket.

BTW, Dave Hotmman is the ruby expert, after seeing what he brought to diamondhead, wow! (you can hear what a properly timed ruby sounds like anyway)




Yeah, mine doesn't sound anything like that- mostly just a solid plume with little definition. 

Ps- yes, using cylinder oil.


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## David Leech (Dec 9, 2008)

Posted By Steve Shyvers on 06 Feb 2012 11:12 PM 
Even a length of plastic tubing can be used as a make-shift stethoscope to listen for steam leaks. The end of the hose can be positioned near glands and unions, and can be very effective to isolate sources of leaks. I have used a length of tubing to diagnose piston ring blow-by in a two-cylinder oscillator. I used compressed air at low pressure and turned the engine over by hand. 

I learned also when testing that these small locomotives seem to behave better under compressed air than under steam, even though the air pressure at the compressor is a lot less than the steam pressure in the boiler. I've had steam engines run great on air, even with significant piston blow-by, but then were non-runners on steam. I'm not sure of all the factors why, but believe that one main one is because the compressor can supply a comparatively much greater volume of air into the cylinders, even at low pressures, than the typical little boiler can supply of steam. Also air does not condense in the cylinders and steam does, which can rob it of a significant percentage of its volume. these small locos with little unlagged cylinders have proportionally huge thermal losses compared to larger cylinders on larger locos. (Ratio of surface area to volume.) 

Steve 

Now, I have not been, nor am I familiar with Ruby, but my experience with compressed air and steam is the reverse.
Since steam will continue to expand once in the cylinder, I have found that it smooths out the running.
A test of a loco that will 'just' run on air, will then run better on steam.
At least that is what I have found.
Interesting how in this hobby we all find out what works best for us.
All the best,
David Leech, Delta, Canada


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## HeliconSteamer (Jan 2, 2008)

Ray, 
If you are getting an ill defined stream of exhaust, I would check the reverser piston. From what you describe, that sounds to me like the culprit. Good luck. 

Paul


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## Ray Cadd (Dec 30, 2008)

That's my hunch. I figure I can adjust the throw by hand, by lifting the j-bar past the stops if needed.


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## Phippsburg Eric (Jan 10, 2008)

Ray -- 

that too would be my first try..I hope so because it is pretty easy.


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## Ray Cadd (Dec 30, 2008)

Right- path of least resistance and all. The next issue would be, how to fix it if indeed it is the spool valve.


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## Steve Shyvers (Jan 2, 2008)

Ray, 

I believe that Dave Hottman has mentioned in his writings about installing small o-rings on the Ruby reverser valve. Someone else might be able to confirm that. 

Steve


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## Ray Cadd (Dec 30, 2008)

Steve- I seem to remember seeing something about that a few years ago. If anyone has any info on that, would be much appreciated, as far as o-ring placement.


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## Ray Cadd (Dec 30, 2008)

OK........the answer is twofold. A) the reverse valve was considerably out of adjustment, and more critically, B) the piston rings weren't functioning as they should. They were removed and replaced with good old graphite string packing. Operation is much improved. 

The reverse valve, I hadn't noticed...duh. The rings, not so sure why exactly they weren't seating. The OD seemed to be a decent fit, but I suspect the ID was off somehow, and allowing blow by. 

Thought I would post this here, as it may be of help to someone else down the road.








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## Kovacjr (Jan 2, 2008)

I have had to put O rings on one of the new Forneys. Did the cylinder valves and will be doing the reverser as not that is giving some problems. I also re did the tolerances on the piston groove for the cylinder Orings and replaced the Orings with new Silicone. What a night and day difference. I hadnt noticed the vaolves leaking until I cleaned up and put a 3/1 oil on them so if there was loose tolerances thay leaked instead of sealed. The loco orignally ran on its own but with cars it had blowby from the pressure.


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