Lionel Legacy Lionmaster Challenger Question? (another issue?)

Edit, one has a tachometer so it will maintain RPM regardless (within reason), the other has no tachometer and is fed the SAME voltage control as the one with the tach. So if you load the one with the tach, the OTHER will spin faster because the controller is raising the PWM to BOTH motors but only reading the actual RPM on the one with the tach.

Edit, OK, it appears maybe the front motor and gearing is binding. Both motors, being given the same power- should spin about the same. Under load- again you can see imbalance or slip, but your video shows that front motor going really slow with no load.

Imo it's normal. Every 2 motored command control locomotive I've ever had exhibits the same behavior.

Any of the Lionmaster locomotives as well as all dual motored diesels. Once the rear motor is loaded i.e. on the track. The front one will speed up.

If theres a speed difference when the full weight is on the track and you can see the front drivers skidding. Then you have an issue.

Ok thanks I was thinking might be an issue. Is there a fix for that?

When I had the locomotive apart to change the traction tires tonight, with no drive rods attached, the drive wheels rolled freely. I actually thought they were too loose.

Attaching the drive rods with the other wheels added a lot more resistance to me spinning the wheels. Could it be the other wheels on the front truck without traction tires that are binding?

Can I take the truck apart or do I have to replace it?

@ArtsModelTrains posted:

(rear trucks down, front in the air) the locomotive tries to pull out of my hand.

Again rear motor has the tach and thus tries to maintain RPM regardless of load. The controller seeing the motor slow down would apply more power to maintain RPM.

Conversely- the front motor has no tach. It gets the same voltage the rear motor is seeing. If you load ONLY the front motor, at a low to mid throttle position, it only has the voltage or power required to spin the rear motor that is UNLOADED- sot it may be possible to load and slow the front motor significantly- maybe even stall.

Ideally unloaded, both motors should spin about the same speed- again they are given the same voltage, there is no load other than the drag of the gears and truck.

@ArtsModelTrains posted:

Ok thanks I was thinking might be an issue. Is there a fix for that?

When I had the locomotive apart to change the traction tires tonight, with no drive rods attached, the drive wheels rolled freely. I actually thought they were too loose.

Attaching the drive rods with the other wheels added a lot more resistance to me spinning the wheels. Could it be the other wheels on the front truck without traction tires that are binding?

Can I take the truck apart or do I have to replace it?

Try to find and pinpoint the bind. It might require removing the connecting rod screws one axle at a time.

@RickO posted:

Imo it's normal. Every 2 motored command control locomotive I've ever had exhibits the same behavior.

Any of the Lionmaster locomotives as well as all dual motored diesels. Once the rear motor is loaded i.e. on the track. The front one will speed up.

If theres a speed difference when the full weight is on the track and you can see the front drivers skidding. Then you have an issue.

OH interesting, I have not noticed any slipping or pulling issues. The locomotive looks like it is pulling better tonight after I replaced the traction tires.

So maybe this is normal and not an issue I should mess with.

@Vernon Barry posted:

Ideally unloaded, both motors should spin about the same speed- again they are given the same voltage, there is no load other than the drag of the gears and truck.

With all due respect Vernon. I think you may have it backwards. They never spin the same off of the track.

Anyone with another Lionmaster engine or diesel is welcome to test my theory.

Don’t remove any rods just yet. Diagnose the issue by disengaging the motor from the truck, and observe how the truck rolls. Watching for rods & links  that catch & or bind, and any brake shoes, or traction tires catching on things …..Repair or adjust as necessary. Reinstall motor, and rotate flywheel by hand, through one driver revolution both forwards, and in reverse. Observing for any binding spots. Watch for whack a mole motors where there’s too much end play and flywheels bob up and down too much. None of this is real rocket science, do a step by step diagnosis thinking how it works, and reducing any binding.

Pat

@RickO posted:

With all due respect Vernon. I think you may have it backwards. They never spin the same off of the track.

Anyone with another Lionmaster engine or diesel is welcome to test my theory.

OK ran downstairs had two diesels in the track, 1 a legacy SD70ACE, 1 lionchief plus 2.0 ET44AC.

Tested them both the same way, held the front off, then the back. Same result as my lionmaster Challenger. Front truck in the air was spinning but rear truck didn't pull engine out of my hand, but then with the front truck on the track and rear in the air both engines almost pulled out of my hand.

Thanks for the help, unless I hear sounds or see odd wheel slip, no issue and I'm not messing with it.

@RickO posted:

With all due respect Vernon. I think you may have it backwards. They never spin the same off of the track.

Anyone with another Lionmaster engine or diesel is welcome to test my theory.

I fully understand that results can vary. The fact remains, the motors are in parallel from the same source. The trucks have the same gearing, it's the same model of motor and hopefully same production batch. They should match within some reasonable margin.

But again, unloaded, with nothing more than truck friction- one would hope they somewhat match RPM.

I go way back to using Train America Studio and learning from that system any dual motored engine will act that way. The unloaded motor without the tachometer tape will always spin faster. It’s normal.

My LionMaster Challenger did the same thing. I posted here several years ago and no one chimed in. Sent it to a shop and they added a resistor to the front motor.

@Jeff T posted:

My LionMaster Challenger did the same thing. I posted here several years ago and no one chimed in. Sent it to a shop and they added a resistor to the front motor.

any idea what size resistor?  do you have a photo of what they did?

@romiller49 posted:

I go way back to using Train America Studio and learning from that system any dual motored engine will act that way. The unloaded motor without the tachometer tape will always spin faster. It’s normal.

Is the tachometer tape the same as the encoder ring?  In this case the engine with the encoder ring runs faster than the motor without it.

Jeff, I don't see how the resistor did anything for the situation where the rear truck loses traction, the front truck would have even less traction due to the resistor.  This issue of two motors is an age-old discussion that applies to almost all diesels and any of the semi-scale steam with two motors.  The only real way to truly fix this is to have tach feedback on both motors, but we all know that ain't happening!

@ArtsModelTrains posted:

Is the tachometer tape the same as the encoder ring?  In this case the engine with the encoder ring runs faster than the motor without it.

Yes

@ArtsModelTrains posted:

any idea what size resistor?  do you have a photo of what they did?

Your front motor is CLEARLY spinning slower than the rear. Adding a resistor to the front motor would just slow or stop the front motor.

Whatever you do, do NOT add a resistor to the rear motor with tachometer. That would then mess with the speed control feedback loop.

Again, of the 2 people responding- they BOTH had situations where the front motor went FASTER than the rear motor. The video result is exactly opposite.

@Vernon Barry posted:

Again, of the 2 people responding- they BOTH had situations where the front motor went FASTER than the rear motor. The video result is exactly opposite.

It depends which motor has the encoder ring on it as to which spins faster or slower.

I believe the Lionmaster steamers have it in the rear. Diesels may very well have it in the front.

I'm not an expert, just a hobbyist that has done minor maintenance and repair on his own equipment. I've owned 7 cc diesels and 3 Lionmaster articulateds. The operation described by the O.P. was standard issue out of the box on all of them.

I suppose I could have 9 defective locos, but I never had any operational issues.

Not trying to play topper here just trying to avoid the poster fixing something that isn't broken.

@ArtsModelTrains posted:

I have used Loctite to fix the front trucks.

I noticed the gear on the end of the front motor shaft was loose and therefore not driving the trucks.  I read on the forum about using Loctite.  I picked some up, applied a little and now the gear is locked tight to the shaft.  Problem fixed????? Which gear? The gear on the axle or the gear on the motor shaft?

Now I noticed something else but I'm just not sure if it is an issue or normal.  I attached a video so everyone can see the issue.  It appears that when I hold the locomotive slightly above the track (my DIY test track) the rear trucks seem to move much faster than the front. This is not typically normal and given you just repaired the gearing in the front truck that before was not even working, I'm questioning if the fix did not 100% work or imposed additional drag.  Yes, I understand there can and sometimes is a speed difference when unloaded and some indicate that is normal- but the larger the difference- the more one motor may be doing more work.

I also noticed that if I put just the front trucks on the rails slightly holding the rear trucks off the locomotive won't pull as a I apply power but if I do the opposite, (rear trucks down, front in the air) the locomotive tries to pull out of my hand. Perfectly normal in this respect, the rear motor with the tachometer attempts to maintain a commanded RPM, from unloaded to loaded states. As you load it and it slows down, the motor controller feed more voltage to maintain the RPM. The front motor has no tach and is in parallel to the rear motor. If you load the front motor, it just slows down and stalls. Again, it's not feedback driven, so if the rear motor is unloaded, and the front motor is loaded, it's only getting just enough voltage to run the rear motor at the unloaded commanded speed.

Given the front motor runs slower, and you had to repair it, I somewhat question if the repair did not add friction or slippage.

Parts listing https://www.lionelsupport.com/...ive-Only-6308093001,

Note, I am not saying you need this, just saying what is available.

the front drive block is available (costly, but cheaper than a new engine) https://www.lionelsupport.com/...GINE-LM-CHALLENGER_2

Unfortunately, the specified exact OEM motor is NLA

I noticed the gear on the end of the front motor shaft was loose and therefore not driving the trucks.  I read on the forum about using Loctite.  I picked some up, applied a little and now the gear is locked tight to the shaft.  Problem fixed????? Which gear? The gear on the axle or the gear on the motor shaft? - If you look at this picture below, it was the small ball like gear with two shafts coming out of it that was not attached to the front motor that I fixed using loctite.

Now I noticed something else but I'm just not sure if it is an issue or normal.  I attached a video so everyone can see the issue.  It appears that when I hold the locomotive slightly above the track (my DIY test track) the rear trucks seem to move much faster than the front. This is not typically normal and given you just repaired the gearing in the front truck that before was not even working, I'm questioning if the fix did not 100% work or imposed additional drag.  Yes, I understand there can and sometimes is a speed difference when unloaded and some indicate that is normal- but the larger the difference- the more one motor may be doing more work.

When I get some time tonight I'll pull the locomotive apart and take a look to make sure I didn't cause any issues when I repaired that front motor.  I think the motor is ok since that appears to be able to spin freely, I'm going to take a closer look at the front truck to ensure nothing is binding there.

Well oops, sorry, I grabbed links and part info for the wrong challenger. What product number is yours?

@Vernon Barry posted:

Well oops, sorry, I grabbed links and part info for the wrong challenger. What product number is yours?

No problem, I should have included that from the start.

SKU: cs-6-82695

UNION PACIFIC LEGACY LIONMASTER CHALLENGER 4-6-6-4 STEAM LOCOMOTIVE #3977 (GREYHOUND)

@ArtsModelTrains posted:

If you look at this picture below, it was the small ball like gear with two shafts coming out of it that was not attached to the front motor that I fixed using loctite.

Thats the "yoke" for the Liondrive coupling.  The yoke slipping on the motor shaft is also a "somewhat common" issue on Legacy diesels.

Loctite was the correct way to fix it.

@ArtsModelTrains posted:

any idea what size resistor?  do you have a photo of what they did?

Unfortunately I do not. Engine is gone so I can't provide any more info.

@gunrunnerjohn posted:

Jeff, I don't see how the resistor did anything for the situation where the rear truck loses traction, the front truck would have even less traction due to the resistor.  This issue of two motors is an age-old discussion that applies to almost all diesels and any of the semi-scale steam with two motors.  The only real way to truly fix this is to have tach feedback on both motors, but we all know that ain't happening!

My issue was more of the two engines spinning at different speeds. The resistor helped.

Jeff, when they're unloaded a two motored locomotive like the Lionmaster and most diesels will always run the motors at different speeds, that's the nature of having one motor speed controlled and the other free-running.