Lionel Conrail ES44 8098 - Rear Truck Vibration Under Load

This is mechanical, not electronic.  Hard to say the exact cause.  Maybe an out-of-balance flywheel or broken gear tooth?  If it really bothers you, you could throw parts at it.  New motor, flywheel, universal joint coupling, maybe even a new truck block.  Order them all at once, or be patient, save money, and replace one at a time until the noise stops.

Hi Ted -

I am hoping it is a Mechanical issue and Not Electronics - For starters I was thinking to swap the front Truck with the rear truck and see if the noise travels to eliminate the truck assembly from the equation. There are no broken gears as I checked it in free wheel motion. No obvious major wear marks or thinned out or bent gear teeth.

A bad motor does sounds plausible but with the cover removed exposing the volume and switches, the brass flywheel looks pretty steady in operational and no apparent wobbling of the flywheel. Maybe perhaps it is the motor with one bad winding - I will inspect more carefully again.

- Richard

A bad motor can create quite a ruckus, so disconnect the motor from the electronics and use a DC bench supply to run it, slow running at between 1.5-2.0 volts will tell the story as a rule.  If it doesn't run smooth, it's probably bad.

Could be something with the internal gearbox of the truck. Remove that coupling that connects the motor to the axle for the rear truck, and then run the engine again. If it has trouble moving, then it means that either the worm gear is messed up or the gear that meshes with the worm gear is bad.

You could also just spin the wheels manually to see if there's an issue with the internal gearbox, the wheels should spin smoothly without any form of binding. Even a little bit could cause that noise you're hearing.

Thanks guys for your direction to look for - So I will do the inspection of the gear assembly first - Inspect the worm gear and all the moving parts that are not visible before suspecting the motor per Gunnrunnerjohn's Idea. I will lay the loco on the side and just power the loco and pre-load on the wheels to see if I get the vibration. Thank You for the direction - If you think of anything additional please let me know otherwise i will do what MichaelB and Gunnrunnerjohn suggested first. Thanks Gents -

Richard

After listening to the video clips, I started becoming superstitious that my Lionel Southern ES44 is having the same problem. But after listening to my model in my room layout at midnight with complete silence, it appears mine doesn't have the issue. With the engine sounds at 0%, I heard a little bit of that sound. But nothing near as loud as what you are experiencing with your model at around 50% volume and in a room with a lot of background noise.

I believe a little bit of vibrating noise from the trucks is normal, since having complete silence would mean constantly lubricating the gears and axles. I probably would not even hear the very low vibrating sounds with the sound system on. I was also running mine at very low speeds, and in conventional mode.

Is the vibrating sound actually that loud, or did the recording device amplify that sound?

In your picture of the dog bone the screw on the left looks loose,maybe the camera angle is making it look that way. 

Doug

One thing to check, make SURE the motor mount and motor are secure, any looseness in the motor will cause significant vibration and/or binding.

If you think  it's the motor I have an extra one that goes to the es44 rear if you need it it's yours just pay shipping it's new 

Hi Miguel - I will let you know if i need the motor. But first let me look at the other low'hanging fruit items suggested by the other members. 

It could be the drive impeller slipping on the motor shaft.   A link below discusses that problem on a Lionel O ES44AC with photos.  The motor and drive design on your AF is very similar.   Consider removing the coupling and testing the loco without the motor coupled to the truck.  That will rule out the motor and the truck to pinpoint the connection between the two.

Liondrive Slip ES44AC

Rich you got it brother keep me posted 

Steims posted:

It could be the drive impeller slipping on the motor shaft.  

A much too common issue.  I use Loctite Retaining Compound to stick them back on.

My Conrail heritage unit makes the same noise so I look forward to hearing about a solution.  Also out of the rear truck.  

Forum;

Thanks STEIMS and Everyone -- After inspecting and tugging on the impeller it appears it is not the problem. The impeller is on tight and there is no play or problems related to the impeller. 

My next step in troubleshooting is to remove the DC motor plug and solder 2 wires onto the PC board and add a DC power supply onto it and try to place a load on the motor and see if the motor is defective or perhaps has a bent shaft.

-- Richard