Bachmann Online Forum

Hi, I need advice on my Bachman 2-8-0.  I've had this loco since 1999 or 2000, most of that time spent in the box.  It ran fine on DC, then I decided to drop a Tsunami into it.  After a difficult fit, I was able to get the decoder and speaker in the tender.  The Tsunami was programmed, sound worked, and it made it around the loop a couple of times.  Then ti started acting up, stalling and jerking when it did run.  I removed the Tsunami, put the jumper plug back in the tender, and returned it to DC operation.  It still stalls.  I can see sparks around the front truck on the tender, especially around the wiper.  All connections appear intact.  I cannot find any reason for these sparks, but apparently this is what is causing the problem.  I hope I did not fry the Tsunami...don't think so as I can still read it on the programming track.  Any ideas on what I can do about the short?  I need to address this issue before proceeding further.  Thanks.

Did one of the tender trucks get turned around?  Make sure both insulated wheels are on the same side.

I assume you removed the tender wheelsets while installing the speaker. Look at the wheels, make sure they are installed correctly as Jay mentioned. 

Typically, the tender comes from the factory with the front wheels getting track power from the right rail, the rear wheels picking up from the left rail.  However, I have seen one with the wheels oriented opposite, and the PC board wired accordingly.

If you have one or both of the front wheels wrong, and the axle pickup wiper is only making intermittent contact, you could also have intermittent shorts.

Notice the wheels have a plastic insulator on one end of the axle.  When installed, front wheels have the insulator on the left side, rear wheels with insulator on right side. (as viewed from the top)

If the wiper is not making continuous contact with the axles, you may have to bend the tabs a bit. Apply a tiny amount of conductive lubricant to the axles for better contact and less friction.

This may not be the problem, but something to check first.

It could be the tender trucks. On my Spectrum 4-4-0 and 4-6-0, one truck picks up on the right rail and one truck picks up on the left rail. I do not have to 2-8-0 so I cannot comment on it.
I have since modified my trucks so they cannot swivel around and short out. I got that idea from the Roundhouse steamer tenders.
Check continuity with a ohm meter.

Rich

On my 2-8-0s with vandy tenders, there were small tabs that only allowed the front tender truck to swivel in one direction, the rear in the opposite direction.  That's ok for going around a left curve, but for a right curve the trucks wouldn't pivot. I don't know what designer (I'm being polite) figured that out.

I removed the tabs and installed new ones so the trucks swiveled both directions, but stopped at just a few degrees.

The USRA tender doesn't have the tabs, but the trucks can only swivel about 20 degrees, then the wheels hit the center channel or the coupler box.

Seems we have to re-engineer everything these days.

Thanks for the replies.  I think we are on the right track...pun intended.  The front truck on the tender did get reversed.  I thought nothing of this, as my old Roundhouse steamers had all of the tender wheels insulated on the same side.  I corrected the front truck, and did apply some 2-26 to the axles and bent the brass wipers down some.  I have ran the loco for 20 minutes in both directions on DC; the only time it stalled was at a creep going through a turnout.  I'm going to try to adjust the wipers some more, and if all goes well, put the Tsunami back in tonight or in the morning.

BTW, this is the USRA tender; my main complaint is that the kingpin holding the trucks on is not big enough, and the trucks often slip off when the loco is picked up.  Thanks again, and I will post my progress.

Quote from: shawneehawk on September 26, 2008, 03:40:59 PM
I'm going to try to adjust the wipers some more, and if all goes well, put the Tsunami back in tonight or in the morning.

BTW, this is the USRA tender; my main complaint is that the kingpin holding the trucks on is not big enough, and the trucks often slip off when the loco is picked up.  Thanks again, and I will post my progress.

If this is a Spectrum 2-8-0, you didn't say?

For the Spectrum 2-8-0 there is NO kingpin holding the trucks in place.  They are held in place by a small bolt up through the truck and a securing nut inside the tender.  You shouldn't really remove the trucks as this may either loosen the nut so that the truck becomes too loose or release the nut so that the truck will be free.

Quote from: rogertra on September 26, 2008, 03:57:17 PM

Quote from: shawneehawk on September 26, 2008, 03:40:59 PM
I'm going to try to adjust the wipers some more, and if all goes well, put the Tsunami back in tonight or in the morning.

BTW, this is the USRA tender; my main complaint is that the kingpin holding the trucks on is not big enough, and the trucks often slip off when the loco is picked up.  Thanks again, and I will post my progress.

If this is a Spectrum 2-8-0, you didn't say?

For the Spectrum 2-8-0 there is NO kingpin holding the trucks in place.  They are held in place by a small bolt up through the truck and a securing nut inside the tender.  You shouldn't really remove the trucks as this may either loosen the nut so that the truck becomes too loose or release the nut so that the truck will be free.

Yes, it is a HO Bachman Spectrum 2-8-0.  My DCC system is the NCE PowerPro.  I only have a test loop set up, 4' x 16', a long loop with 2 passing sidings.  I test DC operations on a 4 x 8 powered by a MRC 2500 and a MRC Control Master 20.

Maybe what I am calling a kingpin is actually a bolt, as it is held in place by the securing nut you described.  As for me removing the truck, I first became aware of this problem when I found the truck and wiper laying loose on the track.  It has not wanted to stay in since.

I put the Tsunami back in, and the sound is fine.  The loco, however, is stalling very easily...at every turnout and going into any curve.  Other decoder equipped locos with sound traverse this same track with zero problems.  So the loco runs pretty good on DC, but stalls easy on DCC.  Help, I am ready to pull my hair (what's left) out.

Make sure the track wipers are correcting installed.

Put the nut back on the bolt, tighten it up so that the truck still swivels easily and secure it with just a drop, on a pin point tip, of AC glue.

That will retain the nut.

The tender pickups are redundant with the pickups from the loco drivers.  So in effect you have 6 wheels on each side picking up current. If you are losing power on curves or turnouts you may have some problems with both the loco and tender pickups.

The reason the Spectrum 2-8-0 works so well on tight curves is because the driver wheelsets can move from side to side to "follow the curve".  In contrast Roundhouse uses blind drivers (flangeless) on #2 and #3.

The loco pickups are long and springy, and as the wheels move sideways, the wipers must maintain contact.

A few years ago, Bachmann made a design change in the "underframe" that holds the wipers. The new "bottom plate" can pinch the wipers, preventing side to side movement to follow the wheels.

The piece should be called the "top plate" as it fits on the top of the assembly.

The change made it harder to reinstall the 2 piece assembly.  The plate is supposed to snap onto the underframe, but when you turn it over to install the assembly, the plate falls off.  To solve this, I fastened the plate to the underframe with tiny optical screws, making sure the wipers weren't pinched in the process.

I consider it a poor design, the "bottom plate" should be on the bottom, so that removing it would allow access to the wipers without removing the assembly. Also, the assembly should be attached to the chassis with separate screws so as to not be unintentionally disturbed.

Turn the loco over and support in a foam cradle. With good lighting move each driver wheelset from side to side and observe the tiny wipers. They could be bent or pinched and not making contact, or there could be excess oil that has coated the inside wheel surface.

I took all my 2-8-0 apart to fine tune them. It is a rather delicate procedure, and not for everyone.  But the wipers should be at least examined.  Sometimes you can use small tweezers to (gently) move the wipers, but if they are pinched, the only recourse is to remove the 2 screws and take off the entire assembly to repair the wipers.  Replacing the assembly takes a lot of finesse, as the plastic "brakes" hang up on the wheels, and the wipers can be badly damaged if you are careless.

If the wipers are badly damaged, order part # H11410, Underframe set with front wheel set, bottom plate, and connector #2.  It's a prewired assembly with the 2 conductor plug on the wires. 

The tender truck bolt has a shoulder that will prevent overtightening, unless you get real brutal with a nut driver.  There should be a small star lock washer under the nut, I prefer a light coating of removeable "Loctite" on the bolt threads.

Good luck

Quote from: Yampa Bob on September 26, 2008, 07:40:47 PM
The tender pickups are redundant with the pickups from the loco drivers.  So in effect you have 6 wheels on each side picking up current. If you are losing power on curves or turnouts you may have some problems with both the loco and tender pickups.

Bob.

There's no such thing as "tender pickups are redundant".

You can never have enough power pickups, steam or diesel, every wheel possible should pick up power.  The more wheels you have picking up power, the less chance you have for loosing contact. 

The Athearn 4-6-2 and 2-8-2 came without tender pickups and were critised for it.

I added brass pickups to my Proto 2000 0-8-0 which originally came withoput pickups.  One of my Spectrum 2-8-0s has a P2K ex 0-8-0 tender and I added power pickups to that and rewired the loco and tender to get power to the motor.  And, of course, I added them to my Athearn steam.

Again, the more pickups, the less chance of a stall due to loss of electrical contact.

I agree you can never have "too many pickups", especially with DCC.  Perhaps I should have used the word "complimentary" or "extra", I was at a loss for a better word.

Technically speaking however I was correct. "Redundant" is defined as "Exceeding what is necessary".  So in that respect, Bachmann is to be commended for going beyond the basics and providing the "extra" pickups in the tenders.

Still, having lots of pickups can't overshadow or minimize the importance of good trackwork and keeping locos well maintained. Whether I have 4, 8, or even 10 pickups I want every single one of them doing their job.

Yes Bob, nothing beats great care taken when track laying

rogertra, thanks; I will try putting a small drop of AC to hold the nut in place.

Bob, I examined the wipers on the inside of the drivers.  When I pushed on one with tweezers, it extended and stuck in the driver spokes.  I ended up having to remove the plate...btw, mine was on bottom.  The wipers looked ok...they are supposed to be bent at a 45 degree angle, correct?  I got the errant one repositioned where it should be.  You're right, the operation involves some finesse, and I had to get the rods corrected on one side.

Anyway, I did get everything back together, or so I thought.  Tested the loco on DCC; got sound from the decoder, but no movement.  I removed the tender shell and decoder and put the jumper plug back in, then tested on DC.  I got a shorting sound immediately from the loco, but could see no sparks.  I did get it to run a foot or so in each direction before it would short out again.  This, after the loco ran almost perfectly on DC earlier in the day.  I might add that the mechanism rolls fine with the motor removed, nothing seems to be binding.

Super-frustrated over what I thought was a simple project.  Thanks for the input; I'll look at the loco again in the morning.

I looked back at your first post, you apparently have the earlier wiper assembly with the cover plate on the bottom. Jim Banner has a pictorial on adjusting the older style wipers, I'll try to find it and post the link.

IIRC from the pictorial, the older wipers were mounted at a 45 degree angle.  The new ones are positioned parallel to the assembly sides, and longer, which provides more side to side flexibility to maintain contact with the wheels.

I have another Connie to modify, I'll take some pictures this time and do a write up on the wipers. I would think the newer assembly would be a retrofit for your loco.

In case you ever want to add more tender wipers, here is what I did with my Spectrum 4-4-0 and 4-6-0 since the tender trucks only pickup on one side. I used Harold's idea.
Harold's site has been gone for over two weeks but I downloaded a lot of his stuff.
Harold's photo.
(http://i98.photobucket.com/albums/l267/richg1998/obj74geo74pg1p33.jpg)

Bottom view of my tender.

(http://i98.photobucket.com/albums/l267/richg1998/Tenderwithmicro-Tsunami3.jpg)

The new Roundhouse tender trucks pickup from all four wheels and are designed to limit swiveling in case you ever get a Roundhouse steamer. I am upgrading my older MDC tenders with the new Roundhouse parts.
(http://i98.photobucket.com/albums/l267/richg1998/Roundhouse%20steamers/Newtrucks.jpg)


Rich

Thanks to all for trying to help with this problem.  Sometimes when I get frustrated it is best to walk away for a day or two.  I checked the loco again last night, and am getting the same symptoms...it runs for a foot or two, then stops. 

I am forgetting about the Tsunami for now; this loco now has severe problems on DC.  It has not run right since I removed the bottom plated to check the wipers.  I have rechecked and cannot find the reason for this problem.  The tender trucks and wipers appear ok.  When the loco stalls I do get a buzzing sound around the rear tender truck but cannot find the reason for it.  Perhaps it is the circuit board?????   

Bob, thanks for the reminder about the pickup article.  Here is the link:

http://members.shaw.ca/the.trainman/LV_Workshop/pesky-pickups/ (http://members.shaw.ca/the.trainman/LV_Workshop/pesky-pickups/)

Hope it helps.

Jim, thanks for posting it again.  I hate it when I lose a favorite link.

I'm preparing to fine tune another Connie, this time I'll take some pictures of my bottom plate modification.  On the last one, I was tempted to trim the brakes a bit, pesky little critters.

In checking the wipers in the bottom plate again, I found that the end of one easily broke off.  Looks like I will be ordering part # H11410 tomorrow...Bob, you think the new one will fit on my loco?

The new underframe comes prewired with a plug, and should fit ok.  When you snap on the "bottom plate", make sure the wipers move freely before installing the assembly. 

Sometimes while assembling, the plate falls off.  If it does, tie it on with a couple pieces of thread.  Once in place, cut the threads and pull them out.

Take your time and watch all the wipers while assembling. They tend to hang up on the wheel rims.  You will need fine tweezers to gently move the wipers in place on back of wheels.  Slooooow is the key.

Once in place, start the screws but don't tighten them all the way. Move each drive wheel side to side and observe that the wipers are following the motion to maintain contact.  If one or more wipers dont move with the wheels, the bottom plate has shifted and pinching the long part of wiper along the side channel.  You may have to remove and start over.

Be careful not to bite your tongue in the process.  :D

Dear All,

This may not be exactly the problem with this case, sorry if it is a distraction. (I have not thoroughly read this entire thread.)

I seem to recall a case (thread) where a DCC socket in a tender was shorted where its pins were soldered to the PC board.

It just so happened that those shorted pins imitated the DC jumper (shorting) plug, so it ran fine in DC, but failed when you plugged in a DCC decoder. 

Moral of the story: inspect for solder bridges on the PC board.  Another possibility: wires soldered to the wrong place on the PC board. 

Hope this helps. 

Sincerely,

Joe Satnik   

Thanks, Joe, for jogging my memory.  On one of my Connies, there was a solder bridge in the connector plug at the front of the tender. I used a thin edge file to carefully remove the bridge.

Now I make it a practice to inspect the plug, visually or with an ohmmeter, of any new locomotive before attempting to run. My "pre-inspection" list is growing as new elements of "Murphy's Law" show up.

As I mentioned in another thread, I never place a new locomotive on the tracks without a thorough inspection of everything that might be a potential problem.

Thanks, Joe.  I checked and could find no solder bridges.  I have wondered if there was something wrong with the circuit board.

The loco ran fine in DC until I removed the bottom plate and tried to adjust the wipers.  I have ordered the underframe replacement, and hopefully that will do the trick.  If it doesn't, I will have to send the loco and decoder off to be inspected and repaired...something I'm really trying to avoid.

This has turned into a comedy of errors.  The new bottom plate arrived, and I was able to get it positioned.  Thanks for telling me about the string trick, Bob.  BTW, the new one was identical to the one being replaced.  The loco continued to run erratically.  At first it ran good in forward, but wouldn't hardly budge in reverse.  Then I was able to get it to run in reverse but not forward.  Now, the front truck on the tender appears  frozen, and will not swivel.  I took the nut off the top, and the screw holding the truck will not remove.  It looks like it has melted the plastic around it.    ??? ??? ???

Looks like I would have to order the tender chassis, tender truck wheels, and pcb assembly to be safe.  I talked with Bachman customer service, and they said to mail it in and they would fix it for $20.  I'm not sure they understood the scope of the problems I've had with this loco, however.  I certainly would not want to send my custom lettered tender and body shell in, too.  The only other option I can think of would be to send it to Tony's, and let them figure it out, including the decoder.  But since I could read the Tsunami on the programming track, I believe it is ok and these are strictly DC issues on the loco.  Anyway, I am getting some money tied up in this loco.

Quote from: shawneehawk on October 10, 2008, 03:18:40 PM
Now, the front truck on the tender appears  frozen, and will not swivel.  I took the nut off the top, and the screw holding the truck will not remove.  It looks like it has melted the plastic around it.    ??? ??? ???

It takes heat to melt plastic.  Electric current flowing through a resistance is the probable source of that heat.  The normal current flowing at this location should not produce enough heat to cause problems.  So we are looking for excessive current, probably caused by some sort of short circuit.  The most likely reason for a short at this point is a reversed tender truck.  A reversed truck picks up current from one rail, feeds it through the truck screw to the tender wiring, and from there it flows to all the wheels on the opposite track.  The contact between the phosphor bronze axle wiper and the center screw is not perfect.  The amount of heat the current produces at this point depends on the resistance of the contract between wiper and screw.  With a five amp booster, it can be as high as 75 watts.

Initially a locomotive with a reversed tender truck may run just fine.  The resistance between the wipers and the axles is enough to limit the short circuit current to an acceptable value, often a fraction of an amp.  But as the wipers wear in, the resistance drops.  The contact is also initially intermittent, that is, the short circuit occurs only intermittently.  With a dc power pack, short circuits of limited duration go unnoticed, unless you happen to have an ammeter in the circuit.  But add a decoder and run the locomotive on DCC and the results are different.  A momentary short circuit will often shut down the booster for a second or two, which does have a large effect on the locomotive.  And the larger short circuit current will often cause the wipers to wear in faster.

A different possibility is a short circuit between the positive (blue wire) lighting output of the motor decoder and the locomotive chassis, wheels or motor.  This would draw extra current through two of the diodes in the bridge rectifier in the decoder, and probably destroy one or both of them instantly.  These diodes would most likely fail to a shorted condition rather than to an open circuit.  Such a short would effectively connect the red and black decoder wires together.  Such a short would be low resistance although not necessarily a dead short.  It could, however, carry enough current to melt the plastic around a truck screw if that screw were in the return path to the rails.  The destruction of the diodes in a case like this can be so fast that they do not leave a burn mark on any shrink tubing around the decoder.  Testing the decoder in a decoder tester or in a known good locomotive would confirm or rule out this scenario.

Jim, thanks for the input.  I examined the tender trucks again and they were in what I believe to be the correct position...looking down, the front truck wheels are insulated on the left,  and the rear truck wheels are insulated on the right.

As far as the decoder goes, I removed the Tsunami almost 2 weeks ago when it became clear the loco had DC issues.  I put the jumper plug back in the tender and have been trying to get this loco running correctly on DC first before proceeding with DCC.

I could find no solder bridges on the PC board, but am wondering if the problem has been the board itself?

Shawneehawk, I have been assuming that your problem has to do with a short circuit as opposed to an open circuit.  But I am not at all convinced that all readers, or even all posters, know what the difference is.  So for the large number of readers who are following this thread, perhaps you will allow me to explain the difference:  (anyone already knowing the difference can skip to the double dashed line below)

Both open circuits and short circuits can stop locomotives dead in their tracks (pun intended.)  But how they stop it, and how they affect locomotive and passenger car lights drawing power from the same source, are quite different.

In general, an open circuit cuts off power to the motor (and maybe the lights) in a locomotive.  An example is seeing the headlights flicker as a locomotive runs down a dirty track.  The lights go off when all of the wheels on at least one side of the locomotive (and maybe the tender) lose contact with their rail all at the same time, creating an open circuit.  The lights come back on when one or more wheels on both sides remake contact with their rails.  Open circuits at other places on the railroad can also stop a locomotive.  These open circuits could be cause by, for example, loss of contact where the locomotive picks up power from its own wheels, loss of contact at one or more rail joiners, loss of contact within turnouts, loss of contact at the power pack or booster terminals, and so forth.  Some times, we even use open circuits on purpose - an example would be an on/off toggle switch to isolate a storage siding.

Open circuits rarely cause heating, and when they do, it is minor because there are still things in the circuit to limit the current flow, like lights and motors.  An open circuit that causes a locomotive to stop at one place on the layout will often show up as an increased brightness in passenger car lights when the passenger car is parked at another place on the layout, and/or it will cause a GOW bulb connected across the output of the power pack or booster to glow brighter when the open circuit occurs.  The only exception would be if the open circuit occurs inside the power pack/booster or in the wiring between it and the GOW bulb.  An open circuit inside the locomotive can shut off just the headlight or just the motor or it can shut off both, depending on where in the wiring it occurs.

A short circuit creates a conductive path around some place where the electric current is expected to do some work.  Kind of like a dog doing an end run around a hoop because it is easier or it is a shorter path than jumping through it.  Maybe calling it a "shorter circuit" would make more sense, but "short circuit" is already used universally.   Because it does not have to do any work, more electric current can flow than should flow when there is a short circuit.  This extra current can produce heat, often enough heat to melt things or destroy circuits like decoders on sound system.  The extra current is often high enough to shut down the over current device built into power packs and booster for their (and your) protection, but not always.  If the short circuit has some resistance to limit the extra current, it can still stop your locomotive by diverting current away from it yet still not shut down your power source.  This is often referred to as a "partial short."  A short circuit that can and does shut down the power source is often referred to as a "dead short," I suppose because it makes everything go dead. 

A short circuit at one place on the layout will often dim passenger car lights or a GOW bulb wired across the power source.  It will never make these lights brighter.  A short in a locomotive will almost always stop the motor and the lights, except for some DCC cases where the decoder will disconnect a shorted motor without affecting the lights.  A momentary short circuit, such as one caused by a long steamers going through a turnout, often causes little more than a momentary blink of the steamer's headlight when running along on dc but may blink every track powered light on the layout when running on DCC.

Understanding the difference between open circuits and short circuits can make a world of difference when trying to figure out why a balky locomotive or a balky layout refuses to work properly.

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Whew!  If you waded through all that verbiage, then good for you.  If you didn't have to, then good for you too.

Now to the case in point.   It would be really helpful if we knew whether the problem was in the tender trucks or in the adapter board or in the locomotive.  As a first step, Shawneehawk, you could set the tender on the tracks with a piece of paper under the wheels to insulate them from the rails.  Then try to run the locomotive on dc.  If it does not run then the problem is in the locomotive or the adapter board or somewhere between the two.  If it does run, then the problem is in the tender, not in the locomotive.   Try the next two test to see if the problem is in the truck(s) or the circuit board.

To melt the plastic around the truck screw, there had to be heat, and lots of it.  This sure sounds like a short circuit, not an open one.  Shawneehawk, you mentioned in your first post that there were a lot of sparks off the lead tender truck.  This is another indication of a short circuit, particularly one involving that truck.  If the problem is a short circuit, the current is most likely being picked up by the lead tender truck and delivered somewhere.  So why not cut out that little game right quick with a pair of side cutters.  If you trace the wire from the lead tender truck to the adapter board in the tender, you will know which wire to cut to interrupt that lead truck's current flow.  I suggest cutting it about 1/2" away from the circuit board so that you can later find it and have enough to join back up if you need to.  If the locomotive still won't run on dc, then cut the wire from the trailing tender wheels in the same way.  If it still won't run on dc, then it is time to get serious and get rid of the adapter board.  We can cover that, and a few test to do before taking that step, in a future post. 

Jim, I certainly do appreciate your post, and those posts of the others who have tried to help me.  I did perform your first test by placing a piece of paper under the tender wheels and applied DC power.  The locomotive did run, so we know the problem is in the tender or board.  It is too late for me to start snipping and soldering wires tonight, so I'll pick it back up tomorrow.

Observations:  the wiper on the front tender truck is damaged, and will have to be replaced...will probably have to get the whole truck assembly.  Also, I noted earlier that there was one brass washer on the back truck, but none on the front...don't know if this could be part of the problem or not.  I'm tempted to send it back to Bachman and let them figure it out, and may ultimately have to do that, but I am learning a few things.

Other observations:  I got out my only other Spectrum, a 2-10-0 (which will also need converted to sound some day), and looked at the tender trucks.  The wheels are insulated in the opposite order as my 2-8-0.  Don't know if that means anything or not.  Then I looked at one of my BLI mikes, and found the tender wheel insulation matched my Spectrum 2-8-0.   

Shawneehawk

In my first post, I briefly mentioned an inconsistency in the tender wiring and wheel orientation, my error for not elaborating with greater emphasis.

Taking a cue from Jim, those who are already well versed in tender wiring may skip the following narrative and jump to the diagram at the bottom.

I have worked on 7 tenders, both Vandy and USRA, that I run on my 2-8-0 Connies.  All but one had the front wheels with insulator left, rear wheels insulator right.  The odd one had the wheels reversed, but the wires from the trucks were wired differently on the pc board.

The usual convention for DC wiring is red for positive, black for negative.  It therefore follows that the "right rail rule" is that the right rail, as viewed from the engineer's perspective looking forward, is positive. (for forward loco movement) Any time the right rail is not positive, the loco will move backward.  This is why (on DC power) two locos will always move in the same direction regardless of their related orientation (nose to nose, tail to tail, or nose to tail)

I have a new 2-8-0 on my bench.  Looking at the 2 wire harness on the bottom of the loco, the red wire is connected to the right wheel wipers, the black wire to the left wheel wipers. So far it appears to be wired as it should be, at least to my satisfaction. 

Now the tender, with the shell off, connector plugs forward. On my version, the red wire from the two conductor plug at the front (left side) is connected to the left solder terminal at the back of the board, which is labeled "power input".  The black wire is connected to the right solder terminal.

There is a red wire leading from the left solder lug to the front truck bolt.  Another red wire is connected from the right solder lug to the rear truck bolt. 

The front tender wheels have insulator left, so the wheels pick up power from the right rail.  The rear wheels have insulator right, picking up power from the left rail. Again, the right rail rule is being followed. 

Now about that oddball that was different. One red wire was from left solder lug to the rear truck bolt, another red wire from right solder lug to front truck bolt.  Apparently a worker soldered them wrong, and just turned the wheels around to compensate, or perhaps they had the wheels wrong, and decided to switch the wires.  Who knows?  The rear wheels were picking up power from the right rail, the front wheels from the left rail.  But since the wires were switched, it works ok. 

The important thing is that you verify the wiring in relation to the wheel orientation, keeping in mind the "right rail rule" as you proceed. Since both the loco pickup wires, and the tender pickup wires all go to the two solder terminals, if either the tender wheels or the wiring is wrong, you will have a short between the rails.  As Jim mentioned, it might be a dead short or a "resistance" short depending on the contact between the wipers and axles, or contact between the wheels and rails, all of which could be intermittent.

Incidentally, on the oddball tender, I changed the wiring and the wheels to match my other tenders. 

Others may not agree with my "convention", but it is the way I do it to keep everything uniform and avoid confusion and/or mistakes.

Sorry about the long winded explanation, but I have learned that you can't assume the factories always follow a standard procedure. I drew diagrams of the tender wiring (both ways that I have observed).  I'm not claiming that either way is correct or not, all my tenders are wired as on the left.

Bob, long winded explanations are fine with me, as I do feel I am learning something here.  I do appreciate everyone's patience with me.

Patience is something I lack.  Last night, even though I knew better, I returned to the basement to give the Connie a final look.  There, at the edge of the layout, in poor light, and with tired eyes...you guessed it...the motor block and chassis ended up in the floor.  The motor block came open, and I had to collect the motor, bearings, worm, screws, and plastic mounts.  This morning, I worked on the chassis, which surprisingly did not appear damaged.  After some effort (and profanity) I was able to get the the motor parts back together and repositioned.  I did have to resolder the red wire to the motor.  Initially there was some grinding, and I feared I had stripped the plastic gear.  Then I realized I had not put the final 2 screws in the bottom of the block, did so, and tested the loco.

The bottom line:  It ran good in both directions, although a little noisier in forward.  Perhaps gear noise, I'm not sure, but nothing appeared binding.  I ran the loco for 30 minutes in each direction and it did not stall.  Once, the tender rear truck wiper and screw fell out...this has also been a problem...and the loco continued running fine on just the grossly contorted front truck pickup.  Perhaps the problem has been in the trucks and wipers all along, as I had to bend the front wiper under the wheels to make contact. 

I just finished examining the tender wiring.  Jim, I am going to skip snipping any more wires for the moment, due to the fact the Connie ran good for an hour.  Bob, I have traced the wires as you suggested.  The front wheels are insulated left and the rear ones on the right. The red and black wires go to the solder terminal as you described.  Then I found the 2 red wires which go from the solder lugs to the truck bolts are reversed.  The red wire from the left lug goes to the rear truck, and the red wire from the right lug goes to the front truck.  Sounds like I should reverse these, right?  I also like everything uniform.

Thanks...I do feel we are getting someplace finally.  At a minimum I will still need to replace the trucks and wipers...just hope I can get the front truck, the one with the melted screw, off without tearing anything else up.  It does not swivel well at all and is a derailment waiting to happen.

If the lugs are wired as you describe, and you don't match the wheels to the wiring, you may still have a potential for a short.  Study the diagrams and use the plan you like best. From my experiences, the score is 6 to 1 in favor of the left diagram.

It would  help if the factory used red and black wires from the solder lugs to the trucks for easier tracing, and included a diagram. As seen above, a picture is truly worth a thousand words.

A major part of troubleshooting is isolating the problem, "Is it the loco or the tender?"  I recently scrapped a Vandy tender for all the parts.  Using the male connector from the tender front, I spliced the black and red pickup wires over to the wires leading back to the motor. By plugging the loco into this adapter, the loco will run on DC without the tender.  In lieu of the connector, you can jumper the plugs from the loco with tiny wires, similar to the jumper plugs that come with the loco in a small bag.  Just be sure the wires are small enough so as not to spread or damage the female connectors in the plugs, insulated from each other with tape, and tie the wires up so they don't catch on the rails or turnouts.

Welcome to the "Learning the hard way" club, the largest brotherhood in the world.

Hi Bob

Nice explanation and drawing. Much better than I could ever do. I have seen this Spectrum tender issue in a couple different forums. Some modelers are not aware of the change from tender wheels picking up from only one rail to what the Spectrum does now. I have wanted to draw something like that but never took the time. Good job. I would like to use your information if I ever see this issue in a different forum. Actually, I can just like to this forum since you do not have to login to read like you have to in the Yahoo groups.

Rich

Thanks, Rich.
The diagram was hastily drawn in the wee hours, I'm sure someone could improve on it. Feel free to use it any way you like, hopefully it will help others to avoid a meltdown. 

When I got my first Spectrum 2-8-0 I was anxious to get it running. I only noted the variant while adding weight to one of the tenders.

Rule number two of Murphy's Law states that if there is a way to do it wrong, someone will do it.

While we're on tender wiring, it has always irked me that this loco does not have a backup light.  Any suggestions on connecting one?

Looks like I will be ordering replacement trucks from Bachman.  The small brass washer I found is not even shown in the parts diagram.  Does it go on top of the wipers?

The Connie continues to run well this evening, except for the motor noise when going forward.

Looking at the tender I referred to earlier today, there is a small brass washer under the bolt head, on the bottom.  It might be for better contact between the wiper and bolt, however I wouldn't count on the washers being present on all tenders. You might ask service when ordering the truck.

I have also considered adding a backup light. A friend added a great looking brass light, but didn't disclose the details. Jim Banner has done lighting mods on locos, so he would be best qualified to answer this question.

One of my Connies is noisy going forward, possibly the gear rubbing on the casting. This thread has some information.

http://www.bachmanntrains.com/home-usa/board/index.php/topic,4506.msg37905.html#msg37905

Thanks for the link, Bob.  I spent some time working on the Connie this evening.  I was able to determine that the forward noise was coming from the motor itself, not the gears.  I removed the motor from the block and took the belt off and tested it.  No noise, but when I return it to the block, the noise returns, and I can't find the reason for it.  Could it be that it just needs run more?

It took awhile, but I was able to get the front truck off the tender.  The truck itself looks ok.  I don't know why I did not think of this earlier, but I realized that I've had a MDC Santa Fe Prairie since the mid 80's that is not being used (I model L&N), and I could use the wipers and and probably the trucks from it.  Anyway, I was able to get the truck repositioned and ran the loco in both directions for about 15 minutes.  It is running ok and not stalling or derailing.  It is not shorting and I see no sparks.  Perhaps the motor will quieten once I put the decoder back in.

Now the big question, as I don't want to fry the Tsunami...I hope the motor on this loco is isolated ok, and that I did not miss anything when I got the parts out of the floor and reassembled it.  The exploded view helps, but I know it doesn't cover everything.  I know there are 2 white plastic spacers or screw mounting pads that go between the halves of the diecast block and these are in place...am I missing anything else? 

Well, it appears you have removed all the gremlins and have reached the "moment of truth", but the decision to reinstall the Tsunami is yours to make.

I would be inclined to run the loco on DC power for awhile with the decoder installed to make sure there is no binding or other problems.

You might want to run without the shell on the tender so you can check for excessive heat buildup in the decoder. When running a DCC loco on DC, I always have a DC ammeter installed in one track power lead to monitor the current. 

Good luck

Bob, isn't the 'learning the hard way club' one of the after school clubs from the School of hard knocks?

Yes, and after 70 years I have lots of scars to prove it.   :(

I've just returned from a trip, and have been running the Connie in both directions.  It continues to run well, although the noise is still present.  I did put the Tsunami back in and placed the loco on my PowerPax equipped programming track, and was able to read the manufacturer ID and version, so I take this as a good sign.

I've removed the Tsunami and am going to continue running in both directions on DC for another evening or two, then may plug the decoder back in and see how it does running on DC like Bob recommended.

Thanks again, and I'll keep you posted.

I should clarify one statement I made earlier.  With the decoder installed, and running on DCC power, check the decoder for heat buildup.  Running on DC with the decoder installed, you probably won't get any extra heat, as the decoder is essentially bypassed when on DC power.

Quote from: Yampa Bob on October 21, 2008, 02:43:25 AM
I should clarify one statement I made earlier.  With the decoder installed, and running on DCC power, check the decoder for heat buildup.  Running on DC with the decoder installed, you probably won't get any extra heat, as the decoder is essentially bypassed when on DC power.

DCC decoders running on DC can still generate heat, The decoders are not bypassed when running on DC or I have misunderstood what you mean by bypassed.  The logic circuits are still being used to control the motor and lights. The motor gets pulses from the decoder logic even when the decoder sees pure DC. Some functions no doubt will not work.
The input to all decoders is at a full wave bridge rectifier so this bridge can handle DC and DCC. The motor will not get any pulses until the decoder sees a little over  5 volts DC, the operating voltage for a lot of logic circuits.
The NMRA requires this for the decoders. I have used an Oscilloscope to verify this. Hope this helps.

Rich

The only way to truly bypass a decoder is to unplug it and plug in a dummy plug.  Otherwise, as Rich points out, it is still part of the circuit and still produces heat when you run the locomotive on dc.

In my earlier post, I mentioned monitoring heat while running on DC as well. In my last post I was referring to "EXTRA" heat that might be generated due to the increased current demand of the full decoder functions.

"Bypassed"  was incorrect in the DC context but I did say "essentially", I was alluding to the fact that not all functions were operational.  My error was in the wording, not in understanding.

Anyway, thanks for the correction.

I wanted to post a reply as to what has been going on with my Connie the last week.  I finally located the cause of the loco running noisy on DC.  My DC test layout is a 4x8 with homasote over plywood, and Atlas code 100 tacked to the homasote.  I was powering it with a MRC Tech II 2500 and a Controlmaster 20, with the Tech II being the primary pack.  I also had my Spectrum 2-10-0 out and noticed it was getting very noisy, too.  I switched from the Tech II to the Controlmaster, and the loud buzzing was gone instantly from both locos.  I flipped toggles to put the Tech II back on line and the noise returned.  So apparently the Tech II was going bad all along, and I was going crazy as I thought it was the loco.  Maybe this is the reason some of the plastic melted around the front tender truck as well?  The Tech II is 22 years old, but I always thought those power packs would last forever.

I replaced the tender pickup on the Connie with my MDC pickup.  I had to some difficulty in getting the front truck off, but it looks ok.  After confirming the loco was running ok on DC, I put the Tsunami back in and have been running it around the DCC layout with minimal problems.  I say minimal as it did stall a couple of times, but that could be due to dirty track.  I do think the major problems here have been solved, and want to thank everyone for helping me with the Connie.  I also gained some confidence, as I was able to get the loco straightened out without sending it off someplace to be repaired.  I did note on one of the other threads that my PC board may be the original version, as I do not have the 5 banded resistor where it is shown, but will worry about  this problem later.  I'll check back from time to time...this is a great forum!

Thanks again.