The motor arm on the old vacuum wipers turned through a partial circle, then back, rather than moving through a full circle. Each wiper arm linkage was connected to opposite ends of the wiper motor arm. That way as the motor arm turned one way it pushed both wiper arm linkages out, moving the wiper arms out of the park position and across the glass. Then it would reverse direction and pull the arms back into the park position.
Clear as mud?
Last edited by cletis; 05/12/2011 5:13 AM. Reason: removed Ebay link
