Virginian Allegheny axle binding

I got one of these years ago and frankly when I first ran it I was very disappointed. It would jackrabbit start, slow down badly through curves, and fine throttle response was very poor. Nothing I did seemed to help until I installed a TAS Drop in EOB board (like I said this was years ago). With speed control from the Drop in EOB the engine now runs like a champ, in fact I feel it runs better than my JLC Allegheny. I've kept this engine and mainly run it during are local club shows as it doesn't have a lot of add on detail to get knocked off. Has run reliably for hours and hours.

My question is are you sure you have mechanical binding somewhere? It's a poor runner without speed control. It may be installing an ERR Cruise M will solve your problem.

Ken

Thanks for the response Ken!

Very interesting, I actually had the same reaction. I knew an engine with no speed regulation would run like garbage but I didn't know quite how bad it would be. I actually planned all along to put the ERR Cruise M in this engine along with the JW&A chuff generator and super chuffer. But yeah the way it bucks under certain conditions unfortunately points to binding. It usually doesn't do this so it's probably usable like it is, but whenever the track twists just the wrong way it starts acting up

If it runs smoothly on straight track, highly unlikely it’s an axle binding. ....if an axle is binding, I’d think it would act up no matter what the track is....if you’re having issues going into a curve, I’d look at the articulation parts. If it’s just slowing down in a curve, that would be the nature of the beast, and certainly some modern cruise components will fix this....perhaps a video of it running on straight track, then put it into a curve, may help you get a better diagnosis, or at least a direction to go in.......Pat 

Thanks Pat, video was a great idea!

This first video is on straight and level track. Runs exactly how an engine with no speed regulation should.

In this video you can see the bucking I was talking about. Corners don't cause this problem by themselves, it's uneven track that causes this. But we don't have a permanent layout and we generally leave the trains set up in our basement living room. So the engines have to tolerate a little bit of track twist. All of our Legacy engines run beautifully, including a large AC-12 Cab forward.  Track is freshly cleaned, the layout is powered multiple places. I'm at a loss!

I'd consider some small shims on the axle to keep it from going that far to one side.  I trim bread closures round and use those as shims, slip them over the axle on each side and you should be good.  They come in various thicknesses.

Cut on the red line and slip it over the axle on each side.

Thanks for the info!

The bread clips are an interesting idea. I grabbed a few from my kitchen and gave them a look. They're about twice the thickness then need to be unfortunately. I think my only option is to pull the wheels off and add precision shims. But that option isn't so tempting.

Do you guys know if this was common for these old articulated engines?

 My engine suffered terribly trying to run when I got it. It did some of the things your engine does. Mine didn't stutter as much. It seemed to bind and then would take off at higher speeds until the red TMCC knob was turned down enough to slow it down. Then it would seem to almost stall and do it all over. The loud buzzing noise at every start and slow down drove me nuts!

I tore the stock board set out of my Sunset Allegheny and installed PS2. The engine ran so much better. The PS2 board looks at what the motor is doing and adjusts from that. I think the early TMCC style board set that came in the engine didn't care what the motor or the engine was doing.

I don't think your engine needs any shimming!

"an older 3rd Rail Allegheny with MTH's PS2 control boards and smoke and now the motor control is much smoother. It smokes like a champ in time with the drivers now too. I need to get the right smoke unit for it with the double stack funnel. I'm happy now with the performance of the engine."

I wonder if you could change the settings of the board using the cab 1 so that it ran smoother? starting voltage, etc., like the DCC guys do.

Cut some shims from thinner plastic.

Joe, Wow that thing smokes like a champ! Very nice! And it runs quite smooth! That's interesting our engines behaved in a similar way. I can't say I'm too surprised though, these old engines didn't have speed regulation at all. I totally agree mine needs an ERR cruise real bad! I'm just holding off until I can resolve the bucking.

John, you may know since you're an ERR dealer... the Lionel speed regulation systems use an optical tachometer on the motor to monitor speed for regulation. But the ERR cruise M uses the back EMF of the motor instead. Back EMF is a great way to do that! My only concern is the cruise M only has 2 settings for the motor's internal resistance. I'm confused how the IR can only have a high and low setting though... because usually when back EMF is used the IR must be compensated for very accurately or the resulting RPM will be drastically off. Maybe the answer is 10% error in speed just doesn't matter since these are toys. I was curious what your thoughts were on this.

And yeah i think you're right, appropriate shims would likely solve the bucking problem. Has the clip on shim method worked as a permanent solution for you? I'm a little concerned they would just disappear after a few hours of use

Thanks for your help!

I had shims on a couple of Legacy diesels for years, I eventually sold the engines, but the shims were still intact and working.  The shims were to correct the axle slop that actually allowed the gears to move enough to slip teeth, never had the problem after I finished a couple loaves of bread.

As far as synchronizing different cruise methods, I think that's going to be pretty difficult in any case.  Remember, the speed graph on the Legacy controller for R100 is not calibrated in scale MPH, as the patent for indicating scale MPH is held by MTH.  Retrofit cruise installed after the fact is simply not going to consistently match up with any factory cruise as a rule.

What the ERR Cruise will do for you is allow you to maintain a steady speed on straights, curves, and grades.  I have the same Allegheny that I upgraded to ERR Cruise, it's like a different locomotive.

" I totally agree mine needs an ERR cruise real bad! I'm just holding off until I can resolve the bucking."

I think you have a power pick up issue. The PS2 board I installed in mine resolved many running issues. I think you could help yours electrically first, if you wish to continue with the stock board. I don't see binding in your video. I see power dropping out. I have been wrong many times. 

I think you need to lubricate everything and look closely at the rollers and even main driver and tender wheels, for power loss. The uneven track is telling to me.

After that, maybe you could also set the TMCC board for better performance. The video from Lionel would help.

Joe, I don't believe his issue is simply the lack of speed control.  I've worked on a ton of standard TMCC locomotives without speed control, and anytime I see something like that, I go looking for mechanical issues.

Will,

When the engine stutters, does the headlight, marker lights, and cab lights flash also? If not it's doubtful there is a power pickup problem. There always a chance an internal power wire might be loose. You might check the wire nut connections inside the shell and make sure they are all tight.

Have you tried taking the shell top off and turning the flywheel by hand to try to feel for any mechanical binding?

Ken

Could it be something as simple as a traction tire rubbing on a brake shoe that’s causing the bucking.

Thanks for all the responses guys!

I did some more testing this morning and have some interesting news. I opened the engine up for probably the 5th time, removed the drive shafts and re assembled it. I did this so I could rule out electronics and motor problems. I was able to push the engine around my layout by hand with the worm gears removed and motor disconnected. I was surprised to discover that it had only very minor stiff spots, which seem perfectly acceptable.

Now I'm really confused because the fact the behavior is so different on uneven track really pointed toward axle problems. There's likely a sideways force created by the worm gear and helical gears which is causing the axle shaft to be forced to one side. I was wondering about that all along but wouldn't that sideways force be a problem all the time? not just on uneven track? it seems like track wouldn't effect that at all. I have the same feeling about control problems. I think they would be more consistent.

John, interesting the shims lasted so well! Adding a temporary shim like that probably going to be my next test. I'm more confused now after testing this morning. It sounds like with the ERR cruise there will be some speed discrepancy then, but that's ok. I do like to run lash ups though. The entire reason I got this project was because I couldn't find a Legacy Allegheny for sale anywhere.

Joe, Thanks for the info and video! I'm still convinced based on the bucking that something is grabbing somewhere.

Ken, No the lights stay on very steady. I've had the engine apart 5 times now and it's super simple and spacious inside. I'm convinced there's no loose wires. And the engine wheels aren't even worn smooth yet! They're shiny and new just like the rollers. Which raises another question... do you guys think this thing might just loosen up a bit with more run time? I mean it runs as I would expect it to 90% of the time.

Dave, No I removed those right away when I got the engine. They were rubbing. But they've been off the engine for 3 weeks so it's definitely not those

The very reason I posted, was to point out that's what these old control boards ran like. I can't believe they were even sold like that. It seems unlikely to you right now I know. If you were to upgrade the control boards, the engine would run correctly. That's the very reason they were upgraded.

 They build keep alives into the control boards to smooth out the power interruptions that must drive the electronics crazy.

Why did you make a video with the tender disconnected?

Joe I agree with you! Adding a speed regulation board to this engine would benefit it greatly! TMCC without Odyssey runs just as bad as transformer control. I agree its kind of amazing they offered a control system without an integrated speed controller. It seems that feature is critical to its operation!

I ran no tender because it's an extra 7 axles which could be complicating my problems. This engine only has audio boards in the tender so it isn't necessary for operation.

After further investigation of the axles I found the brass axle bushings have a shoulder which is acting as a spacer between the frame and the wheel. It's so hard to imagine an extra shim would change its behavior.

So I'm going to take your advice and order an ERR cruise M tonight. It seems the next logical step is to slap a speed controller in there and see what happens!

It's a little hard for me to believe that the ERR Cruise is going to fix what I see in that video, but I guess time will tell.  The jerkiness I see in the video is NOT anything I'd expect from a properly running plain TMCC locomotive without cruise.

I agree John! But I don't have any clue what's causing it. I'm thinking at the moment I may need to accept that for an engine of this size and weight I need to level my track better... because I went ahead and shimmed the section of track from the video I took, and it runs fine there now. If I had a permanent layout this would have never been a problem.

I'm wondering if all of Lionel's large articulated engines would be this fussy about track. If this older model is particularly fussy it might make sense to sell this engine to someone who has a table layout.

Does anyone have experience with articulated Lionel steamers acting up on irregular track? I'm particularly curious if the newer Legacy ones do this as well.

I have that same Virginian Allegheny, and before I did the cruise upgrade, it ran fine on my lumpy Fastrack on the carpet.  I have never seen anything like that with any large steam that didn't have mechanical issues.

Well, lets look at it again. He stated it stumbles on uneven track. When he shims that exact track, the engine runs fine. He checked for binding and didn't notice any. I'd have to say that something is causing the engine to stumble like crazy on uneven track.

 So just maybe the power isn't flowing correctly to the board, or the board may have an issue?

I don't see it as you do John. I can't say you're wrong. I just know what I did to fix my Sunset engine that ran that way. It had some type of TMCC board set in it. I have to believe it didn't handle power fluxes, and motor control was poor at best. The engine was totally transformed with the PS2 board set so much that you'd swear it was a new engine. I have to believe that the PS2 battery back-up helped overcome any power loss issues for mine.

doesn't the tender provide any power pick-up to help the engine? 

Joe, the PS/2 battery provides no power at all to the motors, so it wouldn't affect that issue at all.

I'll wait and let this story play out and we'll all know what the end result is.

Yes, I do know that John. The battery keeps the board alive over dirty track and bad spots.

Well I have good news guys! Everyone was right!

I found the main side rods on the rear powered unit to be grabbing intermittently due to sloppy tolerances. The would slip in and pinch between the wheel and spacer (which they were supposed to be on). This only happened under certain conditions so it was tricky to find! The teeth that engage with the wheel were too large and wouldn't fit in the slots intended for them. I filed the teeth smaller and that solved the binding. I missed that the first time I investigated the side gear.

Also with an oscilloscope I watched the engine run with the old controller still in it. I saw a lot of shooting through (big current spikes) for no apparent reason. My best guess is the triacs were sticking open. Good reason to not use triacs for motor control. The cruise commander M I installed uses PWM like the Legacy engines do so it runs like an absolute dream now!

Glad to hear it was sorted out, thanks for coming back and posting the solution.  It's always nice to know how these things are resolved.