Flaky 671 E-unit and motor

My suggestion is to be honest when you list it. From what you describe, the e-unit needs a cleaning and the drum replaced. The e-unit is (in my opinion) the weakest link in the circuit. A gummed up commutator and brush holder can add resistance to the circuit. The e-unit is where the heat builds up first, and the extra heat will melt the e-unit drum pivots, causing the poor erratic connection when cycling it. If you don't want to get it working right yourself, list it as a take-out that works, but appears to need work to function properly. JMHO. Good Luck. 

As I think about it, that makes a lot of sense.  Different E-unit contacts are being used in opposite directions.  I should try the motor with a known working E-unit.  I've got a bunch of E-units, and it could just be a matter of finding one with the right lever and tapping the screw hold that works for the 671.  Then I have a choice: 

1. See what I can do in replacing drum and contacts - ughhh!!! - hate reassembling them, or  2. hire our local expert to fix it.

I've rebuilt many and only had replace the fingers on a few. The older silver contact fingers can be manipulated back to their proper position and shape. They will usually function well with a new drum.

What is your favored technique for putting the D#%$#^d thing back together ?

Everything and more that you ever wanted to know about e-units:

http://www.olsenstoy.com/searchcd31.htm?itm=615

Here are a few teasers:

Some of these Lionel branded tools are collectible and therefore expensive, but I have used Craftsman 4735 snap-ring pliers, KANT-TWIST 401 clamp and a reproduction ST-303 with great success.