If you are talking about the Postwar 2332, you can check out Olsen's Toy Train Parts website. Scroll to bottom of the main page, and there is a banner across the bottom. At the far right is "Library". Click on that, and the first thing after entering the Library, is Postwar Locomotives. Scroll down til you see the 2332, and it will bring up all the pages that came from Service Manuals. From what I just checked, in my K-line manual, the motor is almost identical to the 671 motor. If that is your case, that it is Postwar, then it is pretty straight forward to get it running.
You can test the motor by itself very easily, with a few test cords. Disconnect the wires coming from the E unit, temporarily, but mark which one goes to the Brush Plate contacts. There should be three contacts on the upper part of the Brush Plate. Take one jumper cord and strap the center contact and the right side contact. Take your transformer leads and hook one side to ground of the motor, and then put the other lead to the open contact on the left. Turn the power on, and it should run in one direction. To check the other direction, strap center to left, and transformer lead to the right contact, and it should run the opposite direction.
I would also check the brushes and the armature surface, to make sure it is clean. In order to take the brush plate off, you will most likely have to unsolder the wires anyway. Clean the brush plate surface, brushes, and brush inserts with alcohol. Use a Scotchbrite pad, or 400 grit crocus cloth, and shine up the copper segments of the armature. Also clean the grooves between the copper segments with a toothpick, and reassemble it. It should run with no problem. Granted it is the Postwar version.
If you get the motor to run, with my explanation, then the problem most likely is the E unit, as the culprit. Take it out of the frame, and inspect the drum assembly, and clean up the copper surfaces. Try a Q-tip with alcohol, and check the fingers on the 4 finger board, and make sure no fingers are broken, or bent away from the copper drum contacts. They really aren't hard to fix.