Diagnosing Heritage 2-8-8-2 problem

[peteski]

Assuming that the decoder is still addressable (you can control sound functions) and it is emitting sounds,  in the OPS model write value of lets' say 29 to CV 64.  I human voice should speak the CV number (29) and its value (whatever CV29 is set to).  In the OPS mode, writing a value to CV64 will have the decoder speak the value of that CV.

[mmagliaro]

Hi Mike, The lack of motor function is full time now. It restarted after it's first motor shutdown ,no response since. When attempting to reset, CV 56 will not read or accept changes on either the main in OPS or the program track.

I would suggest disconnecting the motor leads, hooking the motor up to some plain DC to see that it runs.  Make sure the motor itself doesn't have a problem.  I know you're seeing some weird behavior with setting the CV's too, but maybe the motor shorted, shut down  the decoder, and was the root cause of this.  It would be important to at least know the motor is okay.

[TVRR]

Peteski, I changed CV 64 to 9 and got a voice confirmation in OPS mode.  Attempt to write to CV 56 gives a "busy" response.                                                                                                             Max, I'm afraid that taking the loco apart enough to check the motor leads is beyond my level of competence and confidence.

[mmagliaro]

Peteski, I changed CV 64 to 9 and got a voice confirmation in OPS mode.  Attempt to write to CV 56 gives a "busy" response.                                                                                                             Mike, I'm afraid that taking the loco apart enough to check the motor leads is beyond my level of competence and confidence.

Hi (and it's Max, by the way... no problem)...
Have you gotten in to where the decoder is?  You could also disconnect the motor at that end and put power to the leads.   Or does this strictly have to be an "outside the engine, don't take anything apart" kind of diagnosis?

[TVRR]

Max, All the goodies are in the tender so I think I can get it open (ha!). How would I identify the motor leads? The less disassembly required the better, since having my cataracts removed I am leery of small stuff.
 

[mmagliaro]

Well, the standard says that the orange and gray wires from the decoder should be the motor leads.   But looking at photos of the inside of the 2-8-8-2 tender on the Spookshow website, it's all done with nice neat DCC plug/socket, so all the wires are black.  You could unplug the decoder, and then if you could figure out which two wires on the plug go to the motor, you could hook power to those. 

However, the boiler shell should just lift off after removing a couple of screws.  I think it would be a easier to lift the boiler off and disconnect at the motor itself.  Once you disconnect the motor leads, you'd be safe to touch some leads directly to the motor to see if it runs okay.

I'm not trying to beat a dead horse about this.  It just seems to me that in addition to checking all sorts of possibilities with a decoder, it's important to back up a minute and make sure the fundamentals of the engine actually work.  Even if you decide to replace the decoder, it really would be best to make sure everthing works before putting another decoder in there.

[TVRR]

Sounds like a plan, I'll try it and see what happens.
Later this PM   Looked at Spookshow's invaluable site and was delighted to see that one screw under the cab and one in the smokestack are all that holds the body on. I had visions of taking apart a body like the Kat Mikes as I did a few years back, in pieces. In the morning when I've got good light and coffee I will try this. Thanks again guys.

[peteski]

Here is the tender of that loco. But it has a new wire harness I built after the original one melted (I was fixing that loco for someone).  I used the correct color codes for my harness (not all black).    But as you can see, there is no good way to tap inot the motor leads.  The connectors are very small.



Maybe inserting pieces of solid wire into the connector unplugged from the decoder, then attaching some alligator clips?  But one has to be careful not to spread out the female connector contacts.

[mmagliaro]

Thanks, Peteski!  Excellent photo.  (And very neat wiring on that repair!)

That's what I thought when I saw the Spookshow photos.  It just seems to me that the motor is pretty accessible on top once you get the boiler off, and it should be possible to disconnect the wires from it and test it.

[TVRR]

In looking at your rewiring job it appears that the motor leads occupy the outer L & R positions of the tender plug. If so,  can I apply power through the corresponding engine plug slots via the conveniently located bare strips on the bottom of the connector? With little probes?

[peteski]

In looking at your rewiring job it appears that the motor leads occupy the outer L & R positions of the tender plug. If so,  can I apply power through the corresponding engine plug slots via the conveniently located bare strips on the bottom of the connector? With little probes?

No, not outer. Those are rail pickups (red and black) Motor connections are 2nd in from each side (orange and gray).  Yes, if you have some probles small enough to make contact, that should do the trick.

The tender connector pintout is as follows:

RED - right (+) rail pickup
ORANGE - right (+) motor lead
BLUE - common positve for the headligth
WHITE - F0F headlight negative lead
GRAY - left (-) motor connection
BLACK - left (-) rail pickup

Thanks Max!   

[TVRR]

Meanwhile back at the ranch, I found some 0.010 bronze phosphor wire and made tiny probes. The motor does run smoothly as ever (whew). BTW the 0.010 wire fits neatly into the engine plug. Since this is now apparently a decoder issue, are replacement decoders available anywhere? Are there reset possibilities we have not looked at yet? I really appreciate ya'll helping.

 

[peteski]

Meanwhile back at the ranch, I found some 0.010 bronze phosphor wire and made tiny probes. The motor does run smoothly as ever (whew). BTW the 0.010 wire fits neatly into the engine plug.
Since this is now apparently a decoder issue, are replacement decoders available anywhere? Are there reset possibilities we have not looked at yet? I really appreciate ya'll helping.

That's a tough one.  Yes, it sure seems like the decoder has lost its "brains".  These decoders were specifically made for that model (although I think it was also used in some Walthers H0 switcher).  QSI Solutions is also not really selling decoders.  Well, there is still QSI. There were 2 parts of the company - I don't remember the details, and one part is still in business.  But that decoder board was custom-made for Walthers.  Of course Walthers sold all their N scale (ex Life-Like) locos to Atlas. You could contact Customer Service/Repair at Walthers and at Atlas t see if they still have some leftover decoder boards.

I'll PM you some Walthers info, and maybe @EmdFan would have some info about parts availability for this loco from Atlas side.

If all else fails, and you want it, I could take a look at it.  I have fixed one of those decoders for a TRW member few years ago.  But that was a hardware failure (burned out transistor). Yours might not be as easy to fix.  I have the QSI Quantum Programmer (used for uploading sound files to those decoders), but not sure if that will help here. 

[EL3632]

QSI decoders get "stupid" after a long period of non use. There is a way to reset them. Essentially they read, but don't do anything else. I do not have enough experience with QSI decoders to guide through this one, but this link seems to be helpful: https://tonystrains.com/news/how-to-rescue-a-faulty-decoder/#:~:text=QSI%20Decoders&text=Some%20use%20a%20magnetic%20%E2%80%9Cwand,of%20the%20whistle%2Fhorn).
If any of this has been stated already, my bad for posting duplicate information.

[mmagliaro]

Glad your motor is good.

So now I am puzzled.  Is it really critical to put that exact same decoder in there as a replacement?  Couldn't you just put in any sound decoder that will fit?   After all, if this decoder isn't really available anymore, why not just bite the bullet and get a new one that is still supported?