Postwar e-unit problem

[Dougaz]

I have a 49/50 Lionel 6220. The e-unit cycles properly, however, after the 6220 moves forward or backward, when the power is interrupted (transformer control handle to off), then when the power is re-applied, the 6220 lurches forward or backwards a few inches in the previous direction of travel before the e-unit cycles to neutral. I have replaced the drum and the 4 prong and two prong finger boards with new parts and the 6220 still has the same behavior. I believe the problem is in the e-unit. I suspect the drum is tight and not rotating easily, but not sure that is the case. Any ideas what is going on and what the fix is? Thanks

[pennytrains]

Are you sure the fingers are only touching one set of contacts at a time?

[ADCX Rob]

Use the direction button and that won't happen... transformer at 7-8 volts.

[Michael6268]

A lot of my PW engines do that. 

As Rob said, use the direction button.

[emdmike]

Thats the sign of a dirty plunger on the E unit or swollen drum from arcing contacts making it get hot. This makes it sluggish instead of snapping up and quickly turning the drum, it goes slower so the engine will lurch a bit.  You can take some old fashioned TV tuner cleaner and spray it on the plunger and the up into the coil tube to flush out any dirty and grime.  Do NOT use oil, WD40 ect lubricate the plunger, it needs to be bone dry of any type of lubricant that can attract dust.  If I get one being difficult, sometimes some dry graphite will help it out.  Another cause can be a swollen drum.  The older drums tend to swell if the contacts have gotten hot from the fingers arcing to the drum contacts due to dirt.  If thats the case, then the E unit needs to be rebuilt.  If I have to spread the E unit to replace the drum, I usually also replace both sets of fingers, fully clean everything and bring the unit back to factory new standards.    Mike the Aspie

[ADCX Rob]

emdmike

...makes it sluggish instead of snapping up and quickly turning the drum...

I have a 2333 that's been doing this since the 1960s, I think I'll just live with it.

[emdmike]

I find some rubbing alcohol on a cotton swab to clean the plunger shaft helps with one that is sticky.  Sometimes, thats all it takes to get it going better.   Mike

[Dougaz]

Thanks EMDmike. I did completely dissassembe the e-unit, cleaned the plunger with alcohol and a scotchbrite pad and it looked good. Also replaced both finger boards and the drum with new parts. This made the problem a little better but it is still present. 

By the way, i noted your screen name of EMD Mike. Any chance you worked for the Electromotive Division of GM? 

[lionelsoni]

The behavior you're experiencing is unfortunately all too typical.  I have two suggestions:

o  Use a different driving technique.  When going from forward or reverse to neutral, turn on the transformer voltage as abruptly as you can.  There will probably still be a little jerk before the e-unit switches, but less than it might have been.

o  Install a voltage-dropping element.  Get a bridge rectifier unit rated at a few amperes and any voltage, connect its + and - terminals together, and wire the ~ terminals in series with the motor.  A good location might be in series with any of the three wires from the e-unit.  (If you're lucky, these are green, yellow, and blue)  This will lower the motor voltage by about 1 volt.  If you need more, just put more rectifier units in series with the first one or in series with any other of the three e-unit wires.

[Postwar Paul]

The symptom you describe is the E-unit solenoid not pulling up quickly. You might be able to remove the shell and watch it to verify.

Here's the good news:

 this may go away on it's own just by running and usage. I have had several Lionel and Flyer engines eventually " loosen up and behave".

Good luck!

Paul

[Flintlock76]

Postwar Paul

 this may go away on it's own just by running and usage.

Not too unusual on locomotives that have been "asleep" for too long.  In my cases a few shots of electrical contact cleaner sped up the "awakening."