Front truck wanders back and forth

Probably out of gauge.

@Ron H posted:

Probably out of gauge.

Any way to adjust it without disassembling the powered trucks?

John

Don't know.

Measure the gauging first, don't start hammering yet.  I doubt you can re-guage them without taking them off.

Rubber tire issue?

Any way you can post up a video of the ailment?

Pat

You need an NMRA gauge to be sure of the gauge. They are invaluable if you run a lot or build or modify a lot, but just adjusting and running the bare truck through curves and turnouts works too.

I measured the back to back distance between the flanges on both trucks.  They all measure 27.5mm which seems fine.  Maybe something else is going on.  I suspended the loco from the center and the front truck hangs down much further than the rear truck.

The design of the bolster has put the pivot point toward the rear of the leading truck.  This is an open invitation for truck hunting.

@Number 90 posted:

The design of the bolster has put the bit point toward the rear of the leading truck.  This is an open invitation for truck hunting.

Well, it picks certain switch points as it wanders.  I assume the truck is assembled properly then.

Can I do anything about it that you are aware of?

Thanks,

John

It's the design of the truck.  If the pivot point of the truck bolster were at the center, or ahead of the center of the truck, then there should be no truck hunting when running forward.  But this design placed the pivot point behind the center point, effectively encouraging truck hunting.  

As far as the tendency to derail on facing-point switches, the best solution I can think of is to adjust each switch so that the point rail fits tightly against the running rail in both normal and reversed positions.

Just to follow up on this, I watched two videos that had this same Lionel Santa Fe Super Chief engine featured and neither one seemed to have the issue of the front truck wandering back and forth as it rode the rails.  Neither reviewer mentioned it either.

https://www.youtube.com/watch?v=-lsW9MeOSp0

https://www.youtube.com/watch?v=XDvMHk6uD1E

That would imply I can possibly fix it.

Does anyone have any idea what I should disassemble and try?

Thanks,

John

@Craftech posted:

LionChief RTR 6-84719  SF Super Chief Set

Tightened pilot but truck and coupler still wander back and forth.

Wheel gauge issue?

Thanks,

John

https://youtu.be/SbYa7NBYyRc

@prrhorseshoecurve posted:

https://youtu.be/SbYa7NBYyRc

His aunt lived in the Bronx apartment on the same floor next door to ours when I was a kid.

John

@Craftech posted:

I suspended the loco from the center and the front truck hangs down much further than the rear truck.

The front truck hangs down at the front because the additional weight of the pilot forward of the truck pivot point creates a nose-down moment. The rear truck is more equally balanced front to rear. But, I don't think that is the cause of your difficulty.

MELGAR

Update:

Found that one of the wheel flanges on the front truck was bent.  Possible previous owner dropped it.

I stupidly tried to straighten it out and cracked it (Cast metal).

Anyone know if the wheels are available? (Checked the Lionel website and the trucks are unavailable let alone the wheels).  Contacted Jeff at The Train Tender to see if he has either.

Thanks,

John

I'm guessing someone that has a bunch of parts around may be able to help you with wheels, @harmonyards may be your man.

@Craftech posted:

Update:

Found that one of the wheel flanges on the front truck was bent.  Possible previous owner dropped it.

I stupidly tried to straighten it out and cracked it (Cast metal).

Anyone know if the wheels are available? (Checked the Lionel website and the trucks are unavailable let alone the wheels).  Contacted Jeff at The Train Tender to see if he has either.

Thanks,

John

Well doesn’t this just look yummy,……😳…..I don’t have any specific Lion Chief parts, but I’m sure I have wheels that can be adapted in a proper fashion. Fortunately, if I’m looking at the pics correctly, it’s just the plain wheel with damage??…can you pull the truck apart and just send me that  drive block?…you can reach me via profile …..

Pat

Follow-up:

Pat (harmonyards) did a fantastic job replacing the bent wheel.  Amazing craftsmanship.

Thank you Pat.    The front truck  wandering back and forth is gone.

Next:  The reason it hangs down so low.

The threads are stripped on the aluminum motor mount where the single truck screw that holds on the truck screws into the bottom of it.

As a result, if you screw the truck on all the way it binds the worm gear and the truck gears won't turn.  I had to clean out the burrs and screw it on just enough so it wouldn't fall off to get it to work.

The loco shorts out on some Fastrack turnouts at the front truck and there is an up and down movement probably due to a misalignment.

I am sure that is why the truck hangs down so low when you suspend it.

Any ideas on how to fix it?  I doubt that the aluminum motor mounts are available.

Actually, it looks like they are Part Number 610-8154-145

John

@Craftech posted:

Follow-up:

Pat (harmonyards) did a fantastic job replacing the bent wheel.  Amazing craftsmanship.

Thank you Pat.    The front truck  wandering back and forth is gone.

Excellent 

Ordered a couple of motor mounts, a spare motor, a couple of screws, and some traction tires.

That should finally do it. 

John

Follow-up:

The parts arrived today so I took the new motor/worm gear and mounted it on a motor mount.  When I went to mesh the motor worm gear with the truck gears it still sat crooked.  Instead of forcing the mounting screw I removed the grease from the truck's worm gear cavity and discovered a fragment from the broken wheel lodged in there where the motor worm gear and truck gears mesh.  It was preventing the motor worm gear from seating properly.

So I removed the fragment and then the assembly mounted straight.  The truck moved when I rotated the motor shaft.

Now the wandering is gone and the truck doesn't hang down as far as in the photo at the beginning of this thread.  Even without the broken truck piece being in there,  the truck gears never meshed properly with the motor worm gear.  Either that or the aluminum motor mount had a stripped truck screw mounting hole preventing it from snugging up properly.

It appears to be fixed so thanks for all the help.  It also has four new traction tires.

John

Excellent follow up on these issues John. This may help someone in the future.

Although, you might be the only one ever with a wheel fragment lodged in the gearbox.😉

There was also an issue with shorts at Fastrack turnouts.  Someone had posted putting electrical tape on the center rail on the straight side which I did, but it didn't solve the problem.  I had to put tape on both the straight and divergent sides as seen below.  That solved the problem.  The trucks have wide flat wheels and they were touching the center rail in tiny spots at the turnouts.  Fast angle wheels probably wouldn't do that.

John