What would cause a TMCC steam engine start to run and then stop after 8 to 16 inch?

@DGJONES posted:

I have a Lionel UP 2-12-2 locomotive with TMCC and Odyssey speed control ( Item 6-38029) that will start to move but after about 8 to 16 inches will just stop but sounds stay on so the engine is not shutting down.  To get it to move again, you have to turn the red knob on the CAB2 all the way back and then crank the speed up again. But it still only goes 8 to 16 inches.  

Any ideas as to what may be causing this?

Failed magnet ring. fixed link https://www.lionelsupport.com/...FLYWHEEL-MAGNET-RING

A failed magnet ring causes a runaway, I don't see it causing this symptom, at least I've never seen the magnet ring do that.

When it comes to a stop. If you hit the direction button and advance the throttle does the engine move in reverse with the same issue ?

@gunrunnerjohn posted:

A failed magnet ring causes a runaway, I don't see it causing this symptom, at least I've never seen the magnet ring do that.

I'll second that!!! When my ring broke the engine took off like a bat out of....

@gunrunnerjohn posted:

A failed magnet ring causes a runaway, I don't see it causing this symptom, at least I've never seen the magnet ring do that.

You absolutely might be correct, I just spent a few minutes grabbing various 6-28xxx series engines I had on hand with Odyssey and the magnet ring, unplugging the sensor and test running to see if they ran away and stopped in motor stall sensing. Sadly, I have not a single 6-38xxx series engine I could test with.

The engine in question is a 6-38029 series, in which over time I believe they made changes to Odyssey firmware and other details- but I do not know what series exactly or model number when stall protection was added.

What I'm getting at is, OK, so 6-28xxxx series might not have had stall detection in the Odyssey motor driver, but at what point or model series was it added? Only later when we jumped into optical rings?

Don, is this something that recently happened to an engine that was OK before or an engine you just received? I have seen this when an older R2LC is installed in place of an later one that it was built with.

Pete

I have worked on hundreds of Odyssey I TMCC locomotives, and every time the magnet ring was broken or the wiring between the motor sensor and DCDS was compromised, the locomotive takes off at full speed.  I don't know for a fact that it was never changed, but I sure haven't seen it.  One of the later TMCC locomotives just came through my hands with a broken magnet ring, the JLC GG1 from the 2005 catalog.  That one exhibited the same behavior I've always seen, warp speed as soon as you cracked the throttle.

OTOH, early Legacy with the DCDS-J motor driver would run a couple of feet and then come to a halt.  After a reset of power cycle, they'd go another couple feet and come to a stop.

If an early TMCC engine undergoes a magnetic ring fracture, is there a fix? Or does it become a doorstop?

@Mark V. Spadaro posted:

If an early TMCC engine undergoes a magnetic ring fracture, is there a fix? Or does it become a doorstop?

Just replace the $1.50 magnet ring. You read that right, less than $2 (provided you bought in bulk previously to spread and dilute the shipping cost).

Edit, OK, so glue and in some cases, a puller to pull the flywheel off the shaft in some engines and then press it back on, all depends on how the flywheel and ring mounting allows replacement.

******provided that is what the actual problem is*****

https://www.lionelsupport.com/...FLYWHEEL-MAGNET-RING

@Mark V. Spadaro posted:

If an early TMCC engine undergoes a magnetic ring fracture, is there a fix? Or does it become a doorstop?

You have to pull the flywheel to replace the magnet ring as it goes on from the bottom.  That's necessary as it has to be exposed to the sensor on the PCB mounted on the motor.

Now for the important tip!  While it's possible to pull the flywheel off the motor without removing the motor, the same can't be said for putting it back on!  If you don't support the bottom of the shaft when pressing the flywheel back on the motor, you'll likely slide the commutator on the shaft and ruin the motor!

Than on to the sticky part.  Many of the TMCC engines from the middle of the TMCC run in the 2002-2004 timeframe have what I like to refer to as the Lionel puzzle trucks.  In order to remove the motor, you have to take the truck apart from the bottom to get at the motor mount screws in order to remove the motor to replace the magnet ring.

Lionel has a solution to this, though it's a somewhat imperfect solution.  They have what they call the fix-it flywheel that has setscrews.  That sounds good until you go to glue the magnet ring on, the lip that aligns the magnet ring is too small!  So, you have to carefully center the magnet ring on the flywheel and glue it down.  I sometimes just eyeball it, but I've also used four cardboard shims to evenly center it on the flywheel for gluing.

Final important tip!  When you orient the magnet ring, it only goes on one way! The little dots you see on one side face away from the sensor PCB.  If you put it on upside down, it will not function.

Vernon - That’s a relief! Thanks!

GRJ - thanks for that informative post!

Both repairs are outside my wheelhouse, and would require professional assistance. Thankfully, this is a “what if” and not a current problem.

@Mark V. Spadaro posted:

If an early TMCC engine undergoes a magnetic ring fracture, is there a fix? Or does it become a doorstop?

How easy it is depends on the flywheel. Most scale steam that has a Pittman motor, the swap is easy as the flywheel is held in with a set screw. On smaller Mabuchi motors follow Vern’s and John’s replies.

Pete

Here is a video of the engine that Don was asking about, and to answer the question, does it react the same in reverse? Yes it does.

Sounds like a discounted locomotive from the Donnie Jones Locomotive Emporium!…

( disclaimer: I’ve bought quite a few pieces from Donnie, super great guy!…always has a boat load of engines at the Carolina shows, )

Pat

My top suspect would have to be the DCDS board, I don't believe the magnet ring can result in that behavior.  A distant second could be the R2LC as it could be sending out bad commands, I have seen that on rare occasion.

I'd swap out the R2LC first as it's a very easy test.

@DGJONES posted:

I have a Lionel UP 2-12-2 locomotive with TMCC and Odyssey speed control ( Item 6-38029) that will start to move but after about 8 to 16 inches will just stop but sounds stay on so the engine is not shutting down.  To get it to move again, you have to turn the red knob on the CAB2 all the way back and then crank the speed up again.  But it still only goes 8 to 16 inches.  Any ideas as to what may be causing this?

Thanks,

Don

As a recap, let's hope it's something simple- especially an engine "new to you" so you have no idea what happened in the past.

https://www.lionelsupport.com/...12-2-3-Cylinder-9000

I would follow the reset procedure in the manual https://www.lionelsupport.com/...ents/73-8029-250.pdf

page 18

Key point below is setting feature code to AUX1 74

Also, note the Odyssey ON/OFF switch status

Also, what mode was your CAB2 setup for?

What does the engine do with the Odyssey switch in the OFF position?

Ok, I tried to post yesterday, but apparently it did not go through.  In working with this engine, I did the reset as described above, then I also ran the engine conventionally.  The reset improved the running for about a min and then it reverted back to the original issue of intermittent movement. I have attached a couple of videos showing me trying to run it in forward and reverse. I also completely reprogramed the engine back into my remote, but that did not help either. In the third video, I ran it conventionally with the command base turned off. It ran fine!  So the issue must be the TMCC. Let me know if anyone has any addtional ideas, Thanks to those that have posted and those may add some advice.

Scott Kelly

1. Engine programmed correctly into the Cab-2 as a steam TMCC engine ?

2. Speed limit setting off ?

3. Train brake slider set to min ?

4/ Momentum set to low ?

My .02 cents is a bad motor driver board. (Like John said.)

I'd start thinking that the TMCC signal is weak, likely the R2LC if no other engine has the issue. TMCC locomotives will stop if they aren't receiving a track signal.  Are any other locomotives having a problem?

Is the headlight blinking when it stops.

I think it's time to swap the R2LC out.

Check for continuity between the handrails (TMCC antenna) and the boiler. If the handrails contact the boiler it shorts out the TMCC signal and the locomotive will have all sorts of issues in TMCC but will run fine in conventional.