I donl't know if this is the correct forum to post this but it seems like an electrical issue. I just got a new Bachmann Spectrum DCC Pennsy K-4 Pacific loco and it is having problems on two curves on my layoout and they are about 32" and 36" radius curves. It gets to one specific spot on each of the curves and the engine stops, shuts the system down for a couple of seconds and then resumes. I have cleaned the track twice and it still does it ALMOST EVERY TIME, but about 20% of the time it will go thru without a problem. I noticed a small blue arc on the larger radius curve but can't tell where it is coming from. I checked the wheels/drivers for gage and they are all in gage. Anyone have this problem and what might be causing it? My other steam engines don't have this problem, even the Big Boy and Y66b.
-Bob
Life is what happens while you are making other plans!
No way is a 4-6-2 wheel configuration that is in gauge going to have problems negotiating 32" and 36" radius curves.
Is the problem occurring at a rail joint? Are there feeder wires at this location where the loco stalls?
Rich
Alton Junction
Can you post a pic of the layout, especially of the section it's happening?
Almost sounds like a reverser problem on a reverse loop
Springfield PA
Bob.
Flip it upside down and look at the little wipers that rub on the back of the drivers. Sometimes they do not touch the driver when going around curves. One could be bent and touching the frame when they should not be.
When I run across something like that I turn off all the lights and run the loco slow and look for the little blue sparks. Once I found a brake shoe touching a driver on a friends brass loco on curves. It was driving him nuts.
Good hunting.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
Hamltnblue Can you post a pic of the layout, especially of the section it's happening? Almost sounds like a reverser problem on a reverse loop
That's a good point HB.
We need to see a track plan.
Could well be a reversing loop.
Is there a turnout involved where the loco is stalling?
locoi1sa Bob. Flip it upside down and look at the little wipers that rub on the back of the drivers. Sometimes they do not touch the driver when going around curves. One could be bent and touching the frame when they should not be. When I run across something like that I turn off all the lights and run the loco slow and look for the little blue sparks. Once I found a brake shoe touching a driver on a friends brass loco on curves. It was driving him nuts. Good hunting. Pete
Pete,
That is another good point. Those stupid copper sheets with the finger wipers that Spectrum uses on its older locos are easily prone to failure. I had to junk a Spectrum loco because Bachmann no longer had that particular spare part.
I just ran the engine (BTW it is a brand new direct from Bachmann 2 weeks ago!) around the layout and the little blue spark I see is coming from the front pilot wheel arcing to the inside of the lower cylinder chest. I took the engine off and looked underneath and the inside of both cylinders is covered with pit marks from the arcing. Apparently the other side is doing it as well, just didn't see it as it was on the opposite side of the engine. There isn't a reverse loop here and ALL my other 19 engines run fine all over the layout.
The point in the curve where this occurs is just as it enters the easment to the straight track. The other area it was stopping is a similar condition coming out of the curve, but that one hasn't done it in the last 15-20 runs. Maybe the pitting on the cylinder is wearing the metal away so it can't arc as bad as it was??? LOL. As far as I can see it is a case of not enough clearance but why would it only happen to mine??? I may just file a small flat on the cylinder and touch it up with some paint.
The other area I have trouble with this engine and only this engine is that it picks the points on one of my Atlas #6 turnouts; again the only engine that does that (and I have 3 big articulated locos). It is also the ONLY Atlas turnout I have. This engine has been a 'Rebel' since I first put in on the tracks! Maybe all the NYC locos don't like a Pennsy on their tracks??
Will keep you posted as I resolve this. Thanks for all the comments so far, but don't stop if you see or think of something that we may have missed.
The pilot wheels? Weird.
If you bought it new directly from Bachmann, you should contact them and return it for a replacement loco.
If you decide to keep it, I would swap the front and back wheels on the pilot truck or maybe even leave the offending set of wheels off and run the loco to see what happens.
Maybe I am going to have to eat my words about out of gauge wheels.
But I would have suspected the driver wheels before I would have even considered the pilot wheels.
I have had lots of problems in the past with pilot wheels derailing but never arcing.
Keep us posted on your findings.
Check the wheel gauge. Every time I have had a car or loco bounce in an Atlas turnout, the wheels were out of gauge. EVERY time. I use only Atlas turnouts and have never had to modify one.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
If the pilot wheels are hitting the cylinders on 32 and 36 inch radius curves then something is definitely off. If the wheel gauge is that far off it would never stay on the track. Perhaps there may be a kink in the curve? I have 2 of them and they can take a 20 inch curve at speed. Could it be that the front truck is upside down or backwards? Does the crescent shaped slot ends in the rear or front?
If you do remove the front truck cut a couple coils off the spring. This will give it a little better tracking and a miniscule amount of traction.
I checked the wheel gage on all wheels; the first thing I did. I looked at the pilot truck to see if it could be on backward but can't really tell which way is correct. I will turn it around and see if that makes a difference. It came from the factory as it is now. I have been running it for about an hour and it is getting better as the time goes by. It only stopped once yesterday in about 30 trips around the layout. I am running it full throttle and it goes through the yard switches (about 6 of them) without a problem.
As far as the Atlas turnout goes I had another thought: It is one of the last two turnouts that have the original thin Tortise throw wire; all the others have .039" wire. It may just not have enough force holding against the outside rail. It is very easy to move the points. But, this is the ONLY loco that does this? Also, after watching it in 'slow motion' speed I can see that the pilot wheels go through but the lead driver is what is picking the points open.
BTW this was a replacement loco from Bachmann for an older one that had out of quarter drivers. I paid $25 for the latest Spectrum model with DCC (will probably replace the decoder later on). They are very good with customer service.
Again, thanks for all the suggestions and comments. You guys are the best.
ABout the only thing a weaker spring is goign to do is make it LESS likely to derail if coming fromt he frog side witht he points set the wrong way, the weaker spring will allow the points to open to let the wheels through rather than trap the flange and force the wheel up and over to derail.
In the past with 'traditional' construction I only ever used the stock Tortoise wire, Atlas turnouts don;t need much force to move the points (unless you glue them shut when ballasting), and the stock wire always worked. For the 4" of foam I now have, I use thicker wire with the servos.
Randy,
I don' t have any doubt that the weaker spring is sufficient to move the points, they move very easily. I took a closer look at the point rail for the diverging track and it looks like the point is slightly lower than the stock rail (If I am using the correct terminology here?). I still don't see why only this loco is having a problem. I just thought a heavy spring would eleminate the possibility of the wheel picking the point open. Because the turnout is in a very dificult location to work on easily I thought I would be better off just replacing it with another that I would test before permenantly installing it.
Getting back to my original issue of the engine shorting out; I put a small piece of Kapton tape on the bottom of both cylinders and haven't had any problems. I also ran it on another section of the layout that has tighter curves (if you call 24" radius 'tight'?) and it didn't short out. I don't see the blue arcing that was there before. This is still a mystery as to why it should happen on this engine and no one else is having this problem. I will contact Bachmann about it to see what they might say. I think my best solution now is to file a small flat on the bottom of the cylinders where the arcing occurs and then repaint it.
Thanks again for all your help and suggestions.
Odd, that size loco on 24" and larger radius shouldn't have an issue with the pilot wheels touching the cylinder - but obviously yours does. I could see that happen squeakign around tighter curves, but 24" should be fine, and your even bigger ones no issue at all. And a #6 turnout is WAY bigger. If you run REALLY slow, does one fo the pilot wheels lift up to come in contact witht he cylinders, rather than it swiveling too far to one side? If it's climbing up, it could be a tight spot int he turnout forcing one wheel up off the rail.
[quote user="rrinker"]
This is really puzzling to me too. I have watched it closely on the large curves and the pilot wheel doesn't move but the arcing occurs at several places in the curve; apparently the curve geometry has a couple of spots where the wheel gets closer to the cylinders. Since I put Kapton tape on the cylinders I haven't had any problems other than the one #6 turnout; that still is derailing (not an arcing issue here). I have a new turnout on order and will replace this one when it arrives. I will test it before installing permenantly. As I mentioned earlier, this turnout is in a very difficult area to work on so I will be doubly sure it works flawlessly and also I can get a better look at the old one when I get it out.
Could the front truck be backwards? There is a crescent shaped slot. The center of the crescent should be forward and the ends point rearward toward the drivers. Holding the loco and looking at the underside with the pilot at the top it should look like a frown. That would also allow it to spark when hitting the cylinders. By rights the pilot should be the same polarity as the frame.
I have checked this out and even compared it to the parts diagram that Bachmann supplies. This was one of the things I looked into early in the game. Don't understand how this is happening but so far the Kapton tape has solved the issue; although the cause hasn't been figured out yet.
thanks for the comments,
Bob
I called Bachmann today and they didn't understand how this could happen. They said I could return it and they would repair or replace. I opted to keep it and just file the corner of the cylinder rather than wait another 6-8 weeks. They said that would be the only solution they would recommend other than returning it.
farrellaa I called Bachmann today and they didn't understand how this could happen. They said I could return it and they would repair or replace. I opted to keep it and just file the corner of the cylinder rather than wait another 6-8 weeks. They said that would be the only solution they would recommend other than returning it. -Bob
If it were me, I would take advantage of Bachmann's offer and let them replace it with a new one.
The other thing you might do is construct a test track with an oval and see if the loco performs similarly off the layout.