Williams power upgrade trucks

[jpstrainyard]

JP of Acton MA, USA writes

I have a postwar lionel Santa Fe F3 AA. The powerd unit has 2 magnetraction motors of the horizontally mounted configuration. Recntly, one of the motors simply stopped running. I took the motor apart, and found nothing wrong, and nothing dirty. It simply just stopped running. My question is, is it possible to somehow retrofit the Williams F3 compatible power trucks on the postwar frame, without much serious mods.

any help or advice would be very much appreciated.

thank you.

[Len]

JP,

The short answer to your question is no.

Unfortunately, there's no way to modify the Lionel frame for their horizontal mount motors to accept the WBB trucks and motors.

Question on the motor that stopped running: When it is mounted to the truck assembly, are you able to rotate the armature by hand so the wheels turn? If so, I would suspect a loose or broken wire to a brush or the field coil.

Len

[jpstrainyard]

Len,

I checked the wiring to all possible solder joints, and found nothing loose or broken. I was able to turn the armature by hand, though. Another thing I checked for was any kind of debris that could have caused a jam, but again found nothing. I also dismounted the motor from the truck so I could look for further problems, but again, found nothing. Could it be that the armature is possibly burned out ? If so, how do I go about replacing it ?

Sincerely: JP of Acton MA, USA

[Len]

JP,

It may just be the motor brushes have worn down to the point the brush springs aren't maintain a good contact any more. If they're worn down to roughly half the depth of the brush holders, you should replace them.

Since you pulled the motor already, it's fairly simple to find out if you have a bad armature winding. Remove the brush plate and brushes from the motor, then use a tootpick to clean any brush residue from the slots between the armature segments.

Use a multimeter set to Ohms and check the resistance between each pair of adjacent armature segments, for three readings total. Touch the leads together to see what resistance, if any, you meter leads are adding first. You should read between 1.3 and 1.5 ohms, not counting any test lead resistance, between each pair of segments. It's okay if it's a little higher, as long as all three readins are fairly close.

If you get a reading of less than 0.5 ohms anywhere, you've got a shorted winding. If your reading an open, you've got a burned out winding. In either case the armature would have to be rewound or replaced.

These folks http://www.trainrefs.com/PartsBin/index.html do rewinding and have replacement F3 armatures for $34.95.

Len

[jpstrainyard]

Len,

After a thorough cleaning of all moving parts associated with the motor, I was able to get it running again. The armature was actually in pretty good shape, so I didn't really need to do much of anything to it. However, if I eventually do need to replace the armature, I would require a special gear puller to remove a gear on the end of the shaft. Unfortunately, after a few test runs, the motor stopped again, so I may have to replace the whole motor if this problem persists. Until then, I'll make further inspection of the moving parts to see if anything might be seriously worn. I checked the brushes, and they were still in good shape and made good contact with the armature.

Sincerely: JP of Acton MA, USA

[Joe Satnik]

Dear JP,

With intermittent wiring or solder joints between the e-unit and the motor eliminated, I'm thinking the brush holders/springs are dirty, or the springs are worn out and need to be replaced.

If you can get the loco off its wheels, and yet get power to the center roller pickup and ground to the chassis, you could wait til the bad motor stops and read the voltages on the brush holders:

Set your DVOM to 20 V A.C.  Connect the black probe to the chassis.

Measure the voltage of the motor brush terminals with the red probe.   

In forward or reverse,  one terminal should be very near the throttle (center rail pickup) voltage.

The other motor brush should be around half the throttle voltage.

In neutral, both are equal voltage.  (More than likely both zero volts, though they could be both "near center rail" voltage.)   

In the other direction, the "near center rail" and "about half center rail" voltages are on the opposite brush terminals.

Report back your findings and readings.

Hope this helps.

Sincerely,

Joe Satnik

[Len]

In addition to what Joe said, did you check the wear of the motor brushes themselves. If you can see half, or more, of the brush holder above the brushes they should be replaced.

Replacements are available from Olsen's Toy Trains (PN: 622-121) for $1.00/pr+S&H. Or you can get brushes with a copper 'wick' imbedded from Lionel (PN: 6108507150) for $1.20/ea+S&H. The wick gets soldered to the brush holder with the e-unit wire so connectivity isn't completely dependent on the brush spring.

Len

[jpstrainyard]

Len,

the brushes are in top shape and are not worn. When I removed the brushes the first time, they were very dirty, as were the brush holders. A simple and thorough alcohol cleaning of the brushes and brush holders removed much of the brush residue. I also thoroughly cleaned the top of the armature (known as the commutator) with alcohol. After putting the motor back together, it still would not spin - even if dismounted from truck. My next approach might be to use a voltmeter to check for any dropouts in electrical flow and/or weak solder joints

Sincerely: JP of Acton MA, USA

[Joe Satnik]

Just thought about something,

The wiring on the good motor brushes will affect the readings on the bad brushes.  (Both sets wired in parallel.)

If you could remove the brushes on the good motor, and make sure the wires that feed the brushes don't touch anything metal, then good readings could be made on the bad motor. 

Hope this helps.

Sincerely,

Joe Satnik

[Len]

If you have some four test leads with alligator clips on both ends, Radio Shacks your friend if you don't, there's a quick way to verify if the problem is the motor or something else.

Disconnect all e-unit wires, leave the field coil wire on the lug between the brushes, and remove the motor from the loco. Put the brushes back if you didn't already.

Connect a test lead from the center lug with the field coil wire to either brush holder.

Connect a test lead from the other brush holder to lug on the side of the motor with the other end of the field coil wire attached to it.

Use the remaining test leads to connect one brush holder to the 'A' terminal of your transformer, and the other brush holder to the 'U' side.

Bring the throttle up slowly and see if the motor starts spinning in either direction.

If the and the ohm readings between armature segments were okay and the armature doesn't move, or moves a little but doesn't spin up, you've got a bad field coil that's not creating enough of a magnetic field for the armature to push against. In which case the motor needs to be replaced, or the field coil rewound.

If the motor does spin up okay the problem is somewhere in the wiring and/or the e-unit. Never forget, there's no rule that says you can only have one problem at a time!

Len

[jpstrainyard]

JP of Acton MA, USA writes:

Today I took ohms readings of my F3's motors. The results are as follows -

Rear motor - the problematic one

measured across brush holder and frame: 2.5 ohms

measured across both brush holders: 1.8 ohms

measured across all 3 commutator contact points: 1.6 ohms



Front motor - the good one

measured across brush holder and frame: 6.0 ohms

measured across both brush holders: 1.5 ohms

measured across front wheels and collector rollers: 2.8 ohms

measured across rear wheels and front collector rollers: 4.3.ohms

on another note, I removed the brushes on the rear motor again, and using a small flat blade screw driver, I managed to clean out the slots (where the springs sit) on top of the brushes. it might have just been that due to residue built up in the spring slots, the springs made poor contact with the brushes. I test ran the train, and both motors seemed to work fine.


Sincerely: JP of Acton MA, USA

[Len]

JP,

As I mentioned earlier, Lionel has brushes with a copper 'wick' imbedded in them (PN: 6108507150) for $1.20/ea+S&H. The wick gets soldered to the brush holder with the e-unit wire so connectivity isn't completely dependent on the brush spring, eliminating the problem you found.

Len