Hi Tom. Good to hear of your progress with the 227. Great little loco. I do not know if you took the e unit apart yet or not. If not that would be my next step. There is a little brass shoulder screw with a nut on the end of it. Remove that screw and the E unit drum will come off the contact plate. Then you can clean up the contacts on the contact plate. Be really careful with the contacts on the drum. They are spring material and are silver plated. Clean them with something non abrasive so not to remove the silver. The black silver sulfide is conductive, so it does not need to be removed. The silver acts a lubricant helping to get the drum to move. The contacts are held onto the drum with tiny drive screws. Lionel had the presence of mind to drill the drive screw holes all the way through the Bakelite, so with a very small punch you can drive the drive screws out and remove the contacts. This would allow you to reshape them. Also I have seen where a new contact was soldered on. I have also seen new home made contacts. With the drum removed you can jumper ajacent contacts to get the motor to run and rule out motor problems.
The wiring should go from the collector rollers to brush plate on the contact opposite the switch that turns the e unit on and off. There should also be a wire directly from the motor field to this point. The other end of the motor field should go to upper rear contact on the e unit. The lower forward e unit contact should have a wire coming from the e unit coil and then ground to the loco frame. The two brush wires should go to the upper forward and and lower rear contacts on the e unit. That is all the wire needed to make the motor run.
As for WD-40, it drys sticky in time. I would never use it on a train. The CRC contact cleaner has been recommended on this site. It is what I use. Let us know how it comes out.
