MTH 44 tonner stalling issues

JDADDY 

I don't know if I have anymore copper left. I used old wipers from an even older Weaver GP38. The two rail copper wipers have a little spring tension to them. I'll  see what I can come up with.

Clem

For what it is worth, the powered axle is split electrically to provide two rail operation on some future model. The electrical connection between the powered wheels is through the 2 rail/ 3 rail switch.

I used a Miniatronics 2 pin connector to wire two 44 tonners together. This worked great until all my bad wiring caused everything to fail. One engine has a rub in one direction. The other has a 60 cycle hum. One of the wire nuts most have come off and the exposed wires hit the speaker. 

44 tonner operators, I remembered another change I did to the 44 Tonner, the pickup rollers, I changed to a wider one, that did not have the insulation on the ends of rollers. They are a MTH part !!  

Need to do both for trouble free operation, in my experience.  

You can see the copper ground wheel wipers also

I think the insulation on the ends were done to prevent shorting problems with certain switches.  I know that some locomotives have issues on our modular layout with Atlas switches, you'll see the arcing marks on them.  The curved switches seem to be the worst offenders.

 My mth 44 tonner might have been a one off. However, it exhibited the same symptoms as have been described on this thread - stalling then shutting down going through certain curves and the curved part of my switches.  However, i noticed it would only happen going in one direction. Removing the shell (not an easy task trying not to bend the rails),  I observed that when the trucks went through a concave shaped curve in the direction that caused my engine to stall, one wire to a motor was too short and was pulling when the truck turned and causing my engine to stop.  Soldering on some more wire and carefully applying some additional solder to the place where that wire attached to the engine cured my stopping while going through certain curves and switches.  It’s been about 3 months of good usage doing switch work around my layout and I haven’t had any more problems with this engine. All of the prior areas where’s it stalled are now passed with ease.  Again, this may have been unique to my engine, but you may want to try running it with the shell off and seeing if the same thing is happening on your engine. 

I added more photos of the wipers....The best one is the one with the fork shape end, it was made out of copper two rail wheel wiper, it has a little spring tension to it,  where as the other one was just a small strip of brass cut off a sheet. You need to put the wider third rail rollers on also.

Clem,

do you know the part number for the wider pickup rollers?

ctr posted:

Clem,

do you know the part number for the wider pickup rollers?

CTR.........I do not know the part number, I switched with a locomotive I have.  I don't remember which locomotive  

Use a box cutter to cut/remove the black plastic insulator ring from the end of each roller.  My B&O unit now runs well over gargraves track and 40 Plus Ross switches.  Stall was caused by loss of power center rail to roller.

Not all stall is caused by center roller,  I changed rollers On my 44 Tonner when they first came out, and still had stalling issues on some turnouts.I put the ground wheel wipers on after the roller change. Seems the larger the Ross turnout the more the problem.. I did not know you could cut the insulated material off the roller, I thought it was a short roller with plastic ends .

Clem 

Before the roller surgery, I requested & received from MTH a set of rollers without the black insulator rings at no charge.  Performance over the Ross switches was a little better but the stalling persisted.  Discussed the issue with Steve Ross B and then told him my next step was to remove the insulator rings, beneath which is a metal recessed groove as if intended for a fat tire.  My theory is that the presence of the black plastic raises up the roller just enuf on some parts of Ross switches to cause the center of the roller to lose contact with the power rail.  Why on this engine?  Maybe more so because of its very short wheelbase.  Larger diesels with these rollers don't seem to have this problem, especially those with 4 rollers.  Its quite possible that the insulator rings were added by MTH to deal with someone else's switch issue, including their own.

I removed the plastic insulators...and...it had no effect on the area my 44 tonner was stalling.  Using alligator clamps, I placed a lead from the outside rail of my Atlas O track to the point at which the truck side frames attached to the 44 tonner and ran it through the point at which the engine stalls.  This had no effect either. 

My conclusion can only be that my switches are not level (for one reason or the other) and the engine's tolerance for such sloppy track work is very small.

Any thoughts??

If someone who REALLY knows how to fix this issue with the 44-tonners (I have had no problems with mine on GarGraves track and Ross switches) is willing to write a step-by-step how-to article that documents the fix (with photos showing each step), I would be delighted to publish it in the magazine. Would get you a couple of hundred bucks

I haven’t had any problems running my MTH GE 44-ton switchers on Atlas O-54 switches and track. The first two videos show New Haven 0807 going through the curved path of an O-54 switch in forward and reverse. The last two show the locomotive facing in the opposite direction and running through the switch in forward and reverse. The locomotive was running conventionally at 11 volts, 0.3 amperes, and a scale speed of 7.2 miles-per-hour with no apparent hesitation on the switch.

Edit: When I posted this on Monday, May 6, 2019, I calculated an incorrect scale speed which has been corrected to 7.2 miles-per-hour as above.

MELGAR

Facing left - running forward

Facing left - running reverse

Facing right - running forward

Facing right - running reverse

Nice videos...I would say you are a lucky man.

My issues with small locomotives is normally in the 5 SMPH range over switches.

I'm with GRJ, speed has to be slow !! 3 smph. or less even starting and stopping on any part of switch.  So far thats what I have after making the roller change and adding wheel wipers. I posted a video on this thread.

Clem

I miscalculated the speed on the four videos I posted above (05-06-2019). The scale speed was 7.2 miles-per-hour and has been corrected in that post. I also tested my MTH New Haven GE 44-ton engine again today and ran it conventionally at 10 Volts, 0.3 Amps, at a scale speed of 5.4 miles-per-hour as shown on the two videos below. (The engine ran around a loop of track with scale distance 1158.6 feet in two-minutes and 26 seconds. That is a scale speed of 7.9 feet-per-second, 5.4 miles-per-hour.) Again, no problem through the Atlas O-54 curved switch path. I recognize that this track geometry is not as critical as a larger-radius turnout and it also has a flat-top rail profile. In addition, the wheels and track are very clean, the track connections are tight, and the track is level.

MELGAR

Facing left - running forward

Facing left - running reverse

Poor ground is partly due to lack of rocking and pitching. The shell interior has very little room for the motors to tilt forward and back or side to side. So the trucks can only swivel. Thus they cannot rock or pitch to keep at least three wheels on the track. It is very likely that under certain conditions, both of the unpowered axles loose contact with the track and that is the cause of the poor ground. (I have not been able to achieve loss of electrical contact between the unpowered wheels and the chassis.) 

Clem -

Looking forward to getting those parts from ya. I very much appreciate it. 

I may just write that article for Allan.

See you Saturday, ill bring my 44 tonners.  

Clem   

I am still working on this stalling issue and my problem is with Atlas-O switches. ( other manufacture’s switches may have similar issues.)

For some reason Atlas chose not to electrically connect the inner outside rails that connect to the frog electrically. In several configurations (as dead end spurs and other complex track arrangements) this means that the frog is not grounded. Running electrical ground to these inside rails powers the frog and allows the non powered wheels to pickup ground much better. So I am in the process of installing grounding wires in all the switches on my UNION FREIGHT switching layout.

With the grounded frog and full width pickup rollers I may have solved my stalling problem.

(I also found that I need to power AND ground the converging rails on my double slip switches.) 

You might ask why do I need to do all this work when the outside rail on the switch is grounded.

As I discussed in a previous post, the trucks have no ability to rock or tilt up or down. So there are many times when only 3 wheels or 2 wheels are contacting the track. Therefore the track has to be powered where the non traction powered wheel hits.

Well that didn’t fix it entirely.

So I removed both traction tires from the front truck. (The rear truck has the tach reader on the motor.) This allows the rear truck with the tach reader to provide ample pulling power.

Now, with four wheel ground on the front truck, my modified 44 tonner crawls through my switches without a stall. And I can run a lash up without one of the engines stalling out.

Additional information: MTH changed the design of the driven axle. Early versions had the two wheels insulated from each other with each having a different electrical pickup that connects through the 3/2 rail switch.

Later models used a solid axle with both wheels electrically connected.

I wonder if we can get the later trucks with the solid axles?  I have no use for the 2-rail option.

Are there any issues using the later model (NEW) 3R Gargraves manual switches?

I just bought a bunch from TK Hobby in Ohio. If there are stalling issues with G.G. I will contact Andy @ MTH to fix the next 44 tonner run prior to production.