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Spontaneous Coupler Opening Solved

 

I had struggled with, and was disappointed with Lionel, when my NP PWC GP kept uncoupling spontaneously.  This is a Legacy engine that is running under DCS wired for TMCC. There’s nothing quite like the sound of the front of your engine smacking into the back of your end car.  I took the engine back to Eastside Trains, and their service tech contacted Lionel.  Supposedly, this is a known problem, and he was told to put a capacitor in the firing wiring.

 

My layout is DCS with the capacity to run TMCC.

 

This didn’t help.  If I turned the engine around and ran it backwards the coupler fired off fairly less frequently, but it still was not safe.  I had to keep a close eye on it.  A common clue was that this seemed to occur over switch tracks (Atlas).  Three out of four of the turnouts weren’t even wired to actuate, and those were the ones that this seemed to happen over the most.  These three are in series; one right after the other.

I had read on the OGR forum that other people had been having the same problem with this engine, so I’m pretty upset with Lionel for putting out a design defect.  And, time went on.

 

I just got a Sunset Models Third Rail NYC T-3a.  This was exciting to me due to the fact that it used to pull my train out of Grand Central station when I’d go up-state with my Mom to the family factory.  (One day when I went to the head of the train to look at the engine pulling the consist I was amazed at the engine; the likes of which I didn’t even know existed).  So, I was excited to get this.

 

I was so excited to have it run that I hooked it right up to the 8 Santa Fe aluminum cars already on the track.  It ran wonderfully well.  I took off the 8 cars and started to build my NYC consist with two MTH 18” cars.  What happened was that the coupler started to open spontaneously.  I was somewhat disheartened thinking that here’s another engine I can’t operate. 

 

I emailed Third Rail and also spoke to Chris on the phone.  He was helpful, and we devised a plan to try and figure out if it was mechanical or electrical.

 

I went up to the train room and took a look at my layout.  I had emailed them that the switches powered feeds were wired in the recommended homerun pattern for DCS.  It had been a while since I had done this so I thought that I should check that out.  I was pretty sure that I did because I’m rather exacting in following plans.  Much to my surprise I found that I had wired the power feeds for these four switches from jumper wires off of a regular homerun wired line.  Well, I thought that this could be the problem (but why with just these two engines).

 

I cut the power feed to the four switches and wired the singular, and most distant one, in a homerun pattern.  Well, guess what.  The engines stopped spontaneously uncoupling.  It worked with both engines running in either direction.

 

So, why didn’t the T-3a not uncouple when I first ran it.  The only reason that I can come up with is that the eight passenger cars with multiple bulbs did the “Magic Bulb” trick on turbo.

 

Why did just these two recently released engines running on Lionel boards (Third Rail’s TMCC & Legacy) have the problem?  Well, the answer is simple.  It’s the electronics.  The particular problem with the electronics is beyond me, but I fixed it.

Perhaps others who are running recent Lionel releases on DCS under TMCC, and who experiencing similar problems should check their wiring to see if they are totally homerun wired.

 

In the end it was my error. So, of course, I’m no longer upset with Lionel.  But, perhaps they should think of this in their designs and put out a bulletin to their service techs.

 

Alan Zend

 

Link to Wikipedia NYC T motors site:  http://en.wikipedia.org/wiki/NYC_T-Motor

Last edited by ajzend
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Alan,  Great advice.  I've been suffering through this problem as well on a new Legacy AC6000 diesel engine that I bought.  this was my first Legacy engine. I too was extremely disappointed to have the engine uncouple after several minutes of running.  I am running the AC6000 Legacy under the 990 Legacy system.  I also have the MTH DCS system on this layout and I am utilizing the home run style of wiring.  I couldn't figure it out for the life of me, so yesterday I got irritated enough at the uncoupling that I took the rear truck off the engine and took the wires off the electro coupler so no power was going to the coupler.  I figured that if anything I could determine if the coupler had an electrical problem or mechanical.  Keep in mind tha I also have a Lionel legacy SD70ACE that runs fine and stays coupled all the time.  I should state that I did send the engine in for coupler repair before trying any of this.  it came back and worked for a bit.  Anyway,  I proceeded to run the engine around the layout pulling 30 cars or so and it worked.   For a while that is.  Eventually I heard the sound of the engine running on its own and the consist sitting on the track waiting for a collision. Good thing I have a large layout and was able to stop the train.  So finally I was able to determine that the coupler has a mechanical problem, not electrical. Disappointed again I simply decided to take the entire coupler off the engine and replace it with a scale Kadee coupler. Takes a little work to get the Kadee on there, but I have enough skill and know how to do it. Not a huge fan of the electro-couplers anyway so this is a minimal if any loss to me.  The scale Kadee looks great and will never come uncoupled. So I guess the problems with Lionel couplers are either electrical or mechanical. It's easy enough to determine, but frustrating.

 

Thanks for posting,

 

Marc 

I'm glad that your problem has been solved.  You will read about spontaneous Lionel uncoupling, but not MTH.  My 3rd Rail that had the uncoupling problem runs under TMCC so it is still kind of a Lionel system.  I know how utterly frustrating it can be to have this problem.
Alan
 
Originally Posted by Marc C:

Alan,  Great advice.  I've been suffering through this problem as well on a new Legacy AC6000 diesel engine that I bought.  this was my first Legacy engine. I too was extremely disappointed to have the engine uncouple after several minutes of running.  I am running the AC6000 Legacy under the 990 Legacy system.  I also have the MTH DCS system on this layout and I am utilizing the home run style of wiring.  I couldn't figure it out for the life of me, so yesterday I got irritated enough at the uncoupling that I took the rear truck off the engine and took the wires off the electro coupler so no power was going to the coupler.  I figured that if anything I could determine if the coupler had an electrical problem or mechanical.  Keep in mind tha I also have a Lionel legacy SD70ACE that runs fine and stays coupled all the time.  I should state that I did send the engine in for coupler repair before trying any of this.  it came back and worked for a bit.  Anyway,  I proceeded to run the engine around the layout pulling 30 cars or so and it worked.   For a while that is.  Eventually I heard the sound of the engine running on its own and the consist sitting on the track waiting for a collision. Good thing I have a large layout and was able to stop the train.  So finally I was able to determine that the coupler has a mechanical problem, not electrical. Disappointed again I simply decided to take the entire coupler off the engine and replace it with a scale Kadee coupler. Takes a little work to get the Kadee on there, but I have enough skill and know how to do it. Not a huge fan of the electro-couplers anyway so this is a minimal if any loss to me.  The scale Kadee looks great and will never come uncoupled. So I guess the problems with Lionel couplers are either electrical or mechanical. It's easy enough to determine, but frustrating.

 

Thanks for posting,

 

Marc 

 

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