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I have a Brass locomotive that previously ran fine, and at home, it also runs fine. However, the last time i brought it to the club, it would run erratically. While it would run at whatever speed it was on the throttle, It would suddenly stop. strangely, if i lowered the throttle settings, (suppose it was on speed step 28), and then increased them, it would start up again. sometimes it would just dead stop.
this is odd, since it ran through this same area of track the very first time i test ran it under DCC, and it ran perfectly.
It is a six axle locomotive equipped with a TCS MC2 decoder. the locomotive looks like only 2 axles on each truck that picks up power, and they only pick up power on one side of the locomotive. However, it runs fine on my layout, and the club had just cleaned the tracks before i put my engine on the tracks (keep in mind that it ran on these same tracks fine when it was dirty). I scrubbed the wheels and got nothing, they looked shiny to start with.
the only thing is that some of my decoders have been behaving funny on the NCE system at the club (some won't even start), yet at home with my MRC Prodigy Express, they run fine, and without issue.
any possible explanations/fixes?
Chris
Modeling New Jersey Under the Wire 1978-1979.
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Might sound strange but have you cleaned the wheels latley?? Brass loco have very poor pick ups from the truck wheels to the loco.
Most of the time they only use one side of the truck wheel on one truck to pick up one rail and then use the other one to pick up the other rail.
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Chris,
Are there differences in how the layouts are wired? For example, if you've got more feeders at home, that might explain why the loco runs funny at the club.
Is anything else different? Do you take the shell off for any reason? Do you change any of the CV's between club and home? Does transporting the loco seem to factor into this problem? Are you coupled to different rolling stock and maybe introducing an intermittent short through the couplers (has been known to happen with brass locos + metal framed rolling stock)?
That's all I can think of for now... Keep us updated!
Andrew
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woodone Wrote:Might sound strange but have you cleaned the wheels latley?? Brass loco have very poor pick ups from the truck wheels to the loco.
Most of the time they only use one side of the truck wheel on one truck to pick up one rail and then use the other one to pick up the other rail.
the engines are brand new, but yeah, i checked, they look shiny. I'll give them an extra scrubbing to be sure.
that is the configuration of pick up on these models. Its annoying, lol. I wish i could wire it up to pick up better. even though its a 6 axle unit, only 4 actually pick up power.
MasonJar Wrote:Chris,
Are there differences in how the layouts are wired? For example, if you've got more feeders at home, that might explain why the loco runs funny at the club.
technically i do, because my small layout used to be block wired, but at the same time, there are feeders and soldered rail all over the club layout. There does not seem to be a loss of power anywhere on it.
Quote:Is anything else different? Do you take the shell off for any reason?
Nope, but i'd been meaning to add weight. the only thing i did change was to add a some traction to a wheel set that didn't pick up power (of the six axles, the leading axle each way do not pick up.) I don't think this could effect it, but that was the only change between the first and second time running. I can always remove this and see how it does.
Quote:Do you change any of the CV's between club and home?
not on this unit, but i've had to do that on some in the past.
Quote:Does transporting the loco seem to factor into this problem?
I put it in it's original box and foam between movements, i don't know if that would effect it.
Quote:Are you coupled to different rolling stock and maybe introducing an intermittent short through the couplers (has been known to happen with brass locos + metal framed rolling stock)?
The car right behind it was one of my Walther commuter cars. While it has metal Kadees, the couplers are mounted right into the plastic, and i cannot see how it would conduct. the weights inside don't extend to the vestibules. the trip pins have been bent up so not to get caught on anything, but it still dies on tangent track with no turnouts or anything.
Quote:That's all I can think of for now... Keep us updated!
Andrew
Have decoders ever acted funny like this on your layout? perhaps my decoder is off. I'll send an Email over to TCS.
Modeling New Jersey Under the Wire 1978-1979.
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Quote:Have decoders ever acted funny like this on your layout?
Sorry - no. The club uses Digitrax, which is what I use at home. I have a TCS decoder in one of my doodlebugs, but it has never given any problems.
One problem I did have with a Digitrax decoder presented itsself in exactly the same way at the club as at home. That one (hesitation and then jumping to a 3-4 mph speed when starting) is apparently a function of the decoder (DH-123??). It's about to be replaced with a sound decoder anyway.
Andrew
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Does the club layout use "dead frogs" on turnouts? Is the club modular? At the modular club that I belong to we have joiner tracks located between modules that are not hard wired to the busses, just relying on rail joiners to make connections. If the rail joiners are loose, steam engines and short diesels will stop on the joiner tracks. Sometimes they will start again on their own and sometimes they need an 0-5-0 nudge to keep moving. Our club does not use the NMRA standard for modular construction although modules built to NMRA standards can be used. We require a 2 inch set back in stead of a 4.5 inch set back on tracks at the end of the module. That allows the use of a 4 inch long joiner track instead of the 9 inch snap track that NMRA standards allow. We have found that most diesels down to an Sw will bridge the joiner and pick up power continuously. A dead frog or even a short length of joiner track with loose connections could cause your problem. If it worked before, but has problems now, it could be that a rail joiner that was tight before has loosened up. The other thing to keep in mind is that dcc is much less forgiving of short circuits than dc. A brief short that a dc loco will go through and keep running will stop a dcc layout. One of our members has a brass diesel; and, found that if the track was at all uneven, the pilot would touch the rails and short everything out.
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Russ Bellinis Wrote:Does the club layout use "dead frogs" on turnouts? Is the club modular? At the modular club that I belong to we have joiner tracks located between modules that are not hard wired to the busses, just relying on rail joiners to make connections. If the rail joiners are loose, steam engines and short diesels will stop on the joiner tracks. Sometimes they will start again on their own and sometimes they need an 0-5-0 nudge to keep moving. Our club does not use the NMRA standard for modular construction although modules built to NMRA standards can be used. We require a 2 inch set back in stead of a 4.5 inch set back on tracks at the end of the module. That allows the use of a 4 inch long joiner track instead of the 9 inch snap track that NMRA standards allow. We have found that most diesels down to an Sw will bridge the joiner and pick up power continuously. A dead frog or even a short length of joiner track with loose connections could cause your problem. If it worked before, but has problems now, it could be that a rail joiner that was tight before has loosened up. The other thing to keep in mind is that dcc is much less forgiving of short circuits than dc. A brief short that a dc loco will go through and keep running will stop a dcc layout. One of our members has a brass diesel; and, found that if the track was at all uneven, the pilot would touch the rails and short everything out.
nope, its got solid track work and the layout is "permanent". I don't know of any dead frogs left on the layout, but even so, this occurs on straight sections of track with nothing on it, even right next to a feeder. I'll try running it a little tommorow at our club train show.
Modeling New Jersey Under the Wire 1978-1979.
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The other thing that can cause a problem is uneven track work that allows some of the wheels to lift off the track. It doesn't need to lift much, just enough to cause the wheels to lose electrical contact.
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I've upgraded these locomotives with better electrical pick ups, and the problem persists. No matter what speed i run it at, it just hits a spot, stops, and hums. it will only run again if i lower the throttle one or two "steps" down.
this doesn't make any sense.
Modeling New Jersey Under the Wire 1978-1979.
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Have you checked the speed CV's..?? It might be that CV's 5 & 6 (high top speed and mid-range speed) are set too low. If all CV's are OK, switch the decoder for another one and see how it behaves with the other decoder.
Gus (LC&P).
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Steamtrains Wrote:Have you checked the speed CV's..?? It might be that CV's 5 & 6 (high top speed and mid-range speed) are set too low. If all CV's are OK, switch the decoder for another one and see how it behaves with the other decoder.
I'll look into it, but the only thing about the decoder i've changed is the address. I would think factory settings would work fine.
Modeling New Jersey Under the Wire 1978-1979.
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Did you ever find the problem and get it fixed?
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Russ Bellinis Wrote:Did you ever find the problem and get it fixed?
no. began to suspect decoder trouble, and so i simply unplugged the decoder at the JST connector, and put an identical one in that previously worked (was plugged into one of my AEM7s). This one proceeded to release large quantities of blue smoke for no apparent reason. I have not yet put another decoder in that engine. I've sent the burned out MC2 back to TCS (thank god for their goof-proof warranty), but i have no idea what its status is.
I've looked over the wiring in my E44A and i still am not sure where the short came from or how to ensure that it doesn't happen again. I think my next step will be gluing paper or styrene against any surface that might allow the wires to short on the frame or shell.
Modeling New Jersey Under the Wire 1978-1979.
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"This one proceeded to release large quantities of blue smoke for no apparent reason....." 
Been there...Done that.... 
Gus (LC&P).
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Coincidentally, the replacement for that MC2 just came in the mail today, but i'm not putting it back into that E44 until i figure out what the story is.
Modeling New Jersey Under the Wire 1978-1979.
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