The insurance in the Electric Booger ran out! So it's go time.
Yesterday I started to change the direction of my "new" series wound motor. The first step was brush timing. According to my measurements, this motor has 11-1/2 degree advanced brush timing. You can see the way the brush holder is advanced when compared to the stator pole centre (the longer line):
Here is how I want it to be timed for reverse direction:
I drilled new holes in the rear cover plate and mounted the brush holder with these new holes. With the end cap installed you can see that I nailed it (probably a fluke):
Here you can see the extra holes in the rear cover plate where the brush holder used to mount:
Now I have to rewire the brushes for reverse polarity. This will involve bending one field connection to mate up to a different brush connection, and modifying one brush cable. Hopefully I will have it running backwards very soon. I will probably run the motor at 12V for two hours to make sure the brushes are seated in properly in their new locations.