Wiring American Flyer K325

The Gilbert engines have a single field wired in series with the armature. If the engine runs in one direction but not the other it is the tender mounted reverse unit. Likely one of the copper fingers used in the reverse position is out of adjustment. The other possibility is the new 4 wire harness was connected wrong. The 5th wire only powers the light and smoke unit, it is not used for the motor.

It is tempting to call a Gilbert reverse unit (also referred to as a remote control unit) an E unit but it is not the same. The Lionel E unit is for motors with double wound fields. Gilbert used motors with double wound fields in some accessories but not in engines.

Thanks Tom. I have used quite a bit of 'tuner cleaner" on the reversing unit but will inspect it closer. The original tether wiring was badly decomposed and I substituted black flexible wire in a tube of heat shrink to keep it neat.  I haven't bothered connecting the 5th wire yet as I knew what it was for and wanted to get the motor running. I've attached a picture of the wiring diagram I found online. I used the center diagram..

I use electrical contact cleaner as well. It sounds like there is a misadjusted or worn out finger on the reverse unit. I mentioned wiring connections because of the comment that you thought the motor was trying to turn in the same direction in the reverse position.

The finger contacts look to be ok. When I get more time, I'll double check that I didn't make a mistake with the wiring. Enclosing the four wires in heat shrink makes it harder to trace them.

Sometimes if you cycle the reverse unit to the non-working direction, a little pressure on each of the fingers in turn will reveal the one that may not be adjusted properly.

Rich

Well, today I removed the boiler shell so I could inspect the wiring to the motor and field. While I had things disassembled I removed and cleaned the armature and everything inside. The wiring looked pristine and was correct. After reassembling I did find I had reversed 2 wires from the reverse unit to the 4-pin plug but it made no difference. The loco still runs backward fine but will not run in the other direction. Perhaps I need to replace the finger units with new ones? The mystery remains.

Cycle the reverse unit to the non running position (not one of the two neutral positions) and touch the fingers as Rich advised.

Tom, I've done this numerous times with no affect.

John T

Ok. If you reverse the two field wires it should cause the motor to spin in the opposite direction when the motor runs. That requires unsoldering the two field connections on either the jack panel or the plug. Flipping them on the plug is probably easier.

Another way is to substitute a known good 5 wire tender for the existing one as a test. That only works if you have another 5 wire engine of any type.

If you turn the engine over and manually spin the armature, (power off) does it spin in both directions for at least one revolution without binding or resistance?

Rich

Is there any  washers present between the armature and bearing cap?

Rich 

Some motors have them and some do not. As long as the commutator does not rub on the ends of the brush tubes it is ok. If it rubs then that will cause problems and a washer must be added.

The last thing I did was remove both reverser fingers and clean them and make sure they were touching the contact surfaces. With the fingers out of the way I could also clean the drum better. No difference. As far as the armature goes, it turns very freely in both directions. I wish I had another 5-wire tender but this is the first American Flyer project I've taken on so I don't have any. Thanks for all your suggestions!

John T.

@JPThut posted:

The last thing I did was remove both reverser fingers and clean them and make sure they were touching the contact surfaces. With the fingers out of the way I could also clean the drum better. No difference. As far as the armature goes, it turns very freely in both directions. I wish I had another 5-wire tender but this is the first American Flyer project I've taken on so I don't have any. Thanks for all your suggestions!

John T.

It seems your only option now is to use a volt/ohm meter and trace the circuit when it is set in the forward direction to see what you have.

Be very sure that the lock out lever is in the run position. Then wire it to a 4 wire hook up. The five wire hook up is for constant lighting and not really necessary if you wire the smoke unit directly to track power. This also lets the motor run more freely from added resistance from the smoke unit & head light.