Recently replaced wiper motor and now wipers will not wipe if both are on windshield; one or the other on the windshield but not both. The wipers will stop and the motor continue to run if both blades on the windshield. I've lubed and tightened cable on both sides. I have gotten them to wipe with both on windshield if the windshield has a continual stream of water. I'm puzzled. For now I'll get along with just wiper on driver's side but would love to solve this problem. Appreciate any suggestions.

Problem may be inside the wiper motor gear box. The main drive gear may be slipping on the drive shaft. Sheared key or bad press fit.
Could be a stripped spline elsewhere?

Is this replacement wiper unit new or used?
If used it may have suffered a icy winter!
If new it could be defective.

You said the motor keeps running as if the wiper were moving and humming like its nobody's business!


Phil

Thanks Phil for your reply. I purchased this motor remanufactured from local parts store. The previous motor just gave out. In fact the old was working, although rather poorly on the day of torrential rain storm but the next morning it wouldn't go any further. I waited a couple of days thinking it might come back to life after things dried out. After testing everything I surmised it was the motor and got a new one. I was a bit taken back that the wipers didn't work! I've spent hours removing stuff to get to the linkage and see if I could tightened it, which I did. Yes, the motor still will try to move the wipers until I turn off the ignition and lift the wipers from the windshield to take any resistance off of it. It really seems like the motor doesn't have as much power to move the linkage as the previous 25 year old motor which had only one speed left in it.

Thanks,
P.T.

Any chance that the wiper arms are not tight on the posts ?

Greg

this could be the result of a weak ground at the motor.

or it could be the grease in the bushings for the wiper shafts/spindles has dried and there's lots of friction. Wile the wipers are switched on try assisting the wiper arm action/motion by hand. How much force do you need to make them move? Are they in synch?
Info and pics are in FAQs referring to www.flametrap.com or cleanflametrap.com?