You may have to remove the brake back plate in order to remove the cotter pin which secures the spring pin.
MT 7 wiper motor 001.jpg (Size: 189.96 KB / Downloads: 211) Both the MT7 (pull and spin) and the DW3 are not polarity sensitive.
MT7.jpg (Size: 142.23 KB / Downloads: 211) The MT7 is not a conventional motor with a commutator, it has a contact breaker which may need cleaning and adjusting, this motor is not self starting and requires the operating knob to be pulled (which makes the contact breaker operational) and spun to start it. The DW3 has a conventional motor and may need the commutator cleaning or brushes changing.
MT 7 wiper motor 001.jpg (Size: 189.96 KB / Downloads: 211) Both the MT7 (pull and spin) and the DW3 are not polarity sensitive.
MT7.jpg (Size: 142.23 KB / Downloads: 211) The MT7 is not a conventional motor with a commutator, it has a contact breaker which may need cleaning and adjusting, this motor is not self starting and requires the operating knob to be pulled (which makes the contact breaker operational) and spun to start it. The DW3 has a conventional motor and may need the commutator cleaning or brushes changing.