Yeah I think starter motors can get over looked, the earth side goes through the first cap then body to brush plate and corrosion between and inside can spoil that path (just to point out to others reading here).
Brush, bearing, seal and o-ring kit is around £50.
Old plate:
![](https://live.staticflickr.com/65535/51954443145_e40d808a03_z.jpg)
![](https://live.staticflickr.com/65535/51954443055_efbccdb23b_z.jpg)
![](https://live.staticflickr.com/65535/51954443255_c0957326df_z.jpg)
![](https://live.staticflickr.com/65535/51954443605_5e194e02a6_z.jpg)
Cleaned with kit fitted:
![](https://live.staticflickr.com/65535/51953844831_8ffc84afe6_z.jpg)
![](https://live.staticflickr.com/65535/51954443475_cf6d4f058a_z.jpg)
![](https://live.staticflickr.com/65535/51953844901_908a1ebee6_z.jpg)
Sorry hijacked your post for a while, just put it on for others that might not have seen inside the starter.