AO Silver Member
Join Date: Mar 2003
Re: Sticking wiper blades
Sorry, just seen your note, "They worked fine all this week. Also it wasnt one positiont they would stop at on the screen it would be various ones up and down the whole cycle."
My best guess is still a worn motor or high circuit resistance. To explain more....
Electric motors generate more torque when they are cold than when they are warm or hot. So when you run them for more than say 15 to 20 minutes they have only about 80% of the torque compared when you first switch them on. So it is not unusual for a worn motor that has been used on a screen with only a slight rain drizzle on a long trip to slow and then stall in the centre of the screen. It would probably still be ok when first used on the morning or when just washing the screen because it would be relatively cold. Engine bay heat can also affect it on a longer journey. The motor only has to reach 50 to 60 deg. C for performance to drop. A motor that isnt worn will not be affected so much.
If its related to wind resistance it should only happen on the down stroke (in the up stroke the wind is helping to move the blades).
Other than a worn motor, an electrical fault that restricts the voltage/current to the motor could have the same effect. Worn switches, relays or connectors that have corroded.
'A business absolutely devoted to service will have only one worry about profits. They will be embarrassingly large.' - Henry Ford.