Lionel TMCC engine stutters and stalls

Besides seating everything, with the wheels free or on test rollers, rotate the flywheel so that the wheels go through at least one complete revolution.  If there is any binding, find and fix that.

 

A bad antenna connection will cause TMCC/Legacy equipment to stop randomly, make sure the handrails do NOT have any connection to the boiler.

 

Another possibility is a bad motor.  I've had a couple of Legacy locomotives recently with bad motors.  One was similar to yours, the other one was a dead short and took out the main board as well, a real meltdown.  I test motors on a test stand disconnected from the electronics using a DC power supply.

 

 A common reason for binding is a loose or incorrectly placed valve gear eccentric. Rotating the motor as John suggested will make this obvious as it will bind in the same place every wheel rotation.

Also spray a little contact cleaner into the pickup rollers. If the engine has sat for a long time there might be some corrosion on the bearing surfaces depending the materials used.

 

Pete

Yep, repaired one of these, the universal is offset from the gear box to the motor flywheel assembly. Its very touchy. There is a support bracket that holds the motor and flywheel, you need to slightly bend it up or down so the universal joint does not bind to the gear box... the universal may already be "chewed up a bit" so you may need to replace it.

Since your losing fire box I would suspect you have a bad power or ground connection or a bad DCDS motor driver

 

Bill

Gentlemen,
   Thanks for all the tips.  I am hoping to open it tonight and I'll let you know what happens.  Thanks again!

Russ

I hope it's not the motor driver, they're kinda' expensive!

Gentlemen,

    Thanks for the help.  So here is an update.  I removed the shell and disconnected the antenna and lights.   I verified the seating of every harness and checked the running gear and drive train for binds and found nothing askew.  I then tested the chassis minus the shell and shell mounted antenna and it ran like a top!!   Put everything back together and the problem came back.   I am thinking it's the antenna.   What are your thoughts and what can I do about it?

 

Thanks,
Russ

Most steam engines use the handrails as the antenna. Check each one with an ohmeter making sure the handrails are not making contact with the shell. If they read infinity (which is good) check them again when you mount the shell to the frame. If the rail fits into the pilot there should be plastic bushings insulating the rail from the pilot. Sometimes these are missing. If so a piece of shrink wrap will work as a substitute.

 

Pete

Pete,

   Thanks for the tip.  I'll check them tonight.   These don't mount to the pilot.  They are only on the boiler.   If they are making contact, what would you recommend as a fix?

 

Thanks,
Russ

If in fact the handrails are the antenna, the stanchions will be plastic. The likely place for a short is where the handrail enters the boiler near the cab. There should be some sort of insulation there either a plastic bushing or shrink wrap. Make sure the antenna wire is attached too, it may just be broken before the handrail.

 

Pete

The handrails on Lionel steamers are virtually always the antenna, I can't recall any that I've seen that aren't.