972 C4 - This is a long shot, but I thought I would ask anyway. I notice what seemed to be variable travel in my windshield wipers. Upon disassembly, I found that between the drive gear and the drive arm, there was a cam of sorts a metal disk with an off center hole. There was spring tension applied to the cam to keep it in place/resist rotation of the cam. In operation, if the cam turns as the drive gear rotates, it effectively reduces the travel of the windshield wipers. If the cam stays in place, the windshield wipers travel the full distance across the windshield. On the road (yes I occasionally get caught in the rain) in light ran when the wipers are under a little more load due to semi-dry windshield and running at the low speed, the travel is reduced to an annoying level which limits the amount of cleared space. In heavier rain, when the windshield wiper has less friction on the glass, the wiper will travel the full distance and clear the windshield appropriately. I have assumed that this is normal and that the travel reducing cam in the windshield wiper drive arm is there to allow more force at reduced travel when the windshield wipers are required to over come more resistance (like in snow?) Has anyone else had a similar experience? Is my wiper system operating correctly? Thanks, Aaron
Mine lift off of the window at speed. However, when they are in contact, they function like yours. Regards, Art S.
Aaron, The purpose of the cam is too push the wipers down a little futher when the wipers are in the parked postion. When you turn the wipers on, the motor will rotate in one direction (I can't remember if it is clockwise or counterclockwise) and the wipers will have the reduced travel due to the cam. This is the normal amount of travel required for the wipers to cover the windshield. When you turn the wipers off, the motor will rotate in the opposite direction and the cam causes the drive cable to be pushed out an extra little bit. This pushes the wipers down off of their normal travel into their parked position. It is normal to have reduced travel with more friction on the glass. As the mechanism wears and gets more slop in it, you get even more travel when the glass is wet. Brian Brown Patrick Ottis Co.
Brian, Thanks for the post it now makes sense I had been puzzling over this for a while Best Regards Aaron