224 Steamer does everything but run

Check the E-unit fingers, they can be temperamental. That is likely where the problem lies. Also check for broken wires at the e-unit.

Odds are that either your eunit rebuild isn't quite right or you have some wires mixed up. It happens to the best of us. Disconnect the E-unit and try running the motor direct. Test power lead to one brush. field wire to second brush, second test power lead to frame. The motor should run.

If it does, check your wiring. Check you E-unit. Do all the contact fingers press against the drum? Is the drum good? Some repro drums have flash covering some of the contact area. Some have misaligned contacts. (Most are fine)

Could it just need more cleaning? If you are still getting dirt off the rollers and wheels, you need more elbow grease...

I've also used Goo-Gone on the armature's commutator plates. Works very well. Clean until no more black comes off. 

Tom 

C W Burfle posted:

...Disconnect the E-unit and try running the motor direct. Test power lead to one brush. field wire to second brush, second test power lead to frame. The motor should run.

Could it just need more cleaning? If you are still getting dirt off the rollers and wheels, you need more elbow grease...

By attaching the test power leads directly to the brushes, and frame, as described above, everything is bypassed but the motor itself. I guess to be really complete, the chassis test lead should go to the solder tab where the field is "grounded.

When I rebuild an e-unit I almost always test it before installation with a little test jig I put together years ago. The last time I skipped the test, the e-unit wasn't right

Another error: Not long ago I did a complete rebuild on an E-unit, only to mix up the color coding of the wires. I mixed up the green and blue on the four contact finger board.
Didn't bother to correct the error, I just hooked it up so it would work and put a little tag inside noting it.