Lionel Steam Turban 2020 won't go in reverse

David JohnstonMember DIGITAL SUBSCRIBER

There are three wires that go from the e unit to the motor. One goes to each of the two brush holders, the third connects to one end of the motor field. The other end of the motor fields is grounded to the motor frame. Disconnect the three wires from e unit to the motor at the motor. These most likely will have to be unsoldered. Then take a power lead from the transformer and connect it to one motor brush holder. Connect the second brush holder to the disconnected field lead with a jumper wire. The frame of the motor needs to be connected to the other transformer lead. The e unit is now out of the circuit. If the motor runs, problem is probably in the eunit. If the motor acts like it is shorted, the problem is probably in the motor.

and the attachment hope that helps

It’s wired wrong.   Move the green wire where the yellow is and move the yellow to the post next to the middle post where there is no wire.   You are only getting power to one side of the motor.  That’s why it will only go forward.  

Still misbehaving.

This should do it. Remove the copper field wire from the outside brush connection, retain the yellow wire on that brush connection.  Reconnect copper field wire to center motor connection with green wire.  Walaa!

Not the problem but on your engine the connecting rod is what powers the other three wheel sets.

Jon

@KOOLjock1 posted:

Not the problem but on your engine the connecting rod is what powers the other three wheel sets.

Jon

Thanks... We took them off when we thought there was a binding issue.  We will reinstall.

Ron

Ron, that copper field wire has to be disconnected from the brush terminal. That’s why it only runs in one direction. Please try as I suggested: remove the field winding from where it is attached now and reconnect it to the middle terminal with the green wire. The E unit will then be able to sequence F-N-R-N-F-etc.

I moved the copper wire.  I can get the engine to cycle into reverse.  But not consistently.  When in neutral is also starts to move again from 6 inches to 4 feet before stopping by itself.  Then another xformer cycle will reverse it.  Sometimes it won’t go neutral or reverse and just stay stuck in forward.

Then sometimes the drive wheel locks up with the worm gear.  I have to manually move the wheel to clear the jam.

Ron

The E unit is now correctly wired to the motor, however, the rotating drum contacts and finger contacts that mate with the drum contacts could require cleaning with a sprayable electric contact cleaner solvent. Also, the pawl assemble which is energized by an electromagnetic coil each time you hit the direction button may be sticking. Was this a new E unit you installed? If not, there’s only one screw holding it in place. Remove it and you’ll have easy access to look it over and spray the contact cleaner. If worse comes to worse, I can send you a replacement E unit, from an upgrade I did, at no cost to you. Good luck.

Are you running the locomotive with a Lionel postwar transformer?  The eunit operates on start up. It takes about 5 volts to get it to work. The postwar transformers turn on at 6 volts to get the eunit to operate before the locomotives starts to move. If you are running the loco on a transformer that has a 0 to15 range, or something like that, the locomotive will start to move, but when the voltage gets to 5 volts the eunit will operate stopping the loco.  Try running the motor with the mounting screws a little loose, the gear mesh might be too tight.  If this fixes the problem you need a thin shim under the front of the motor.  2 or 3 thicknesses of paper might do it.

Thanks Ed B and David Johnson.  I will have my Son try your suggestions.

The xformer is an MTH Z4000.  The e unit is original, but my Son did replace something on it new... I think that's why some wires look new.

Ron

Since you have had the motor off, please make sure that any shims on the bottom side of it did not get misplaced.  They place a critical role in proper engagement of the gears.  They are very thin and easy to miss.

Once you have put the motor back, verify that it turns the wheels easily by hand.

Took motor off again today.  Can I assume these two circles are the shims?  If I put more material over the top of these the gears do not engage.  Put motor back on and it's been running with no jams.

But I suspect the e unit is bad.  My son repaired it last year wanting to keep as many original parts as he could.  But it is so inconsistent.

Right now it's stuck in forward only.  If I play with the switch a dozen times I might be able to get it to F N R.  But it still lurches in N.  Then it will just stop all together.  I have to start playing with the switch again to get it to move.

EdB... Can I buy that e unit from you?

Ron

The #100-25 'E' unit is available here for the 2020 Turbine.

There is a 2 part video tutorial on rebuilding 'E' units if you wish to go that route.

Part 1

Part 2

Larry

Update?

FWIW,

Just watched a you tube on Marx E-units sticking. Person recommended to shoot WD40 near the rod since it's not electrically conductive and may help free a sticking unit. WD40 is not electrically conductive, so your safe there. Not sure if Lionel's the same, but it may help...

@RK posted:

Update?

We can not get it to behave the same way twice.

Sometimes... It will just get stuck in Forward or Reverse no matter what you do to the transformer handle or the switch on the e unit.

Sometimes... It will appear to work normally F-N-R-N-F... etc but in neutral it lurches in the previous direction 6 inches to three feet.

Sometimes... It just sits there unresponsive.

Ron

Interesting issue, E-units are always fiddly things. Is the drum rotating each time you apply power? Can you hear the solenoid engaging each time you apply power?

I would try manually rotating the drum and seeing if each position works correctly. I would also visually inspect the ratchet teeth on the drum - I've worked on one E-unit where all of the teeth were chewed up. Somehow I got it working though.

Rebuild the 'E' unit.

Larry