Why would windshield wipers do this???

[TrainChaser]

My windshield wipers take at least 10 minutes to start working.  I start the truck, turn on the wipers, and wait.  At first they look dead.  Then they move about a millimeter or less.  G r a d u a l l y they go slightly faster.  Then a tiny bit faster than that, slowly creeping up the windshield until they're upright.  In the beginning of this problem, as soon as they got upright and started back down, they would speed up and then start acting normally.  But it's taking them longer and longer to get up to speed.

What kind of problem would make them do this?  I had always thought before that they either worked or didn't work, and if they didn't work, the motor needed replacing.  So what's going on here?

[Scott7022]

My windshield wipers take at least 10 minutes to start working.  I start the truck, turn on the wipers, and wait.  At first they look dead.  Then they move about a millimeter or less.  G r a d u a l l y they go slightly faster.  Then a tiny bit faster than that, slowly creeping up the windshield until they're upright.  In the beginning of this problem, as soon as they got upright and started back down, they would speed up and then start acting normally.  But it's taking them longer and longer to get up to speed.

What kind of problem would make them do this?  I had always thought before that they either worked or didn't work, and if they didn't work, the motor needed replacing.  So what's going on here?

What is it on? The wipers? 

Year, model, brand...


I had an 1970 Datsun we stuffed a 289 ford motor in that did the same thing and it was because we added a variable wiper circuit to the system. They would do that for about five minutes and then work like normal.

We left it as you had to reverse hard and then open the driver's door otherwise it would stick and not open. Read frame twist so we knew she was not long for the world...

[Blacktank]

weak motor and/or goo/ruff windshield surface

[GotSmart]

Bad motor or connection.

[snikwahpn]

Also could be a problem in the switch. I have had "intermittent" wiper switches that are supposed to be variable lose the variation and only have the slow and fast, with nothing in between.

[TrainChaser]

1992 Ford Ranger.

I don't think it's the surface -- I've cleaned it and then applied Rain-X water repellent.

Once it gets going properly, the speeds vary normally.

[Scott7022]

It was an earlier Ford harness we spliced into on the 289 conversion that had the intermittent wiper option. It did the same thing exactly. I would guess it is the device that times the current application to the wiper motor. We never really set out to find it as in BC it always rained enough to use slow setting. LOL! Sorry, I wish I could be more helpful.

[GotSmart]

This might just be me, but I love to take things apart.

[sternwake]

First clean the connector at the motor. It might get its electrical ground from the firewall to which it is mounted.

This stuff is magic electrical juice:

https://www.amazon.com/CAIG-Laboratories...+deoxit+d5

In the past I have linked the Caig DeOxit D5 spray, the link above is the full strength solution D100 with a brush applicator. The d5 spray should be pink tinged. My last can of D5 does not leave the pink residue on a paper towell or Qtip, and it does not appear to be as magical.

The brushes and the commutator in the motor could be glazed too. A few light taps on the body of the motor with a hammer might yield a response. but definitely clean the connector first and perhaps loosen and retighten the mounting bolts to reestablish the ground path. preferably with a bit of D100 on the bolt threads.

No other electrical contact cleaner will touch actual electron occluding oxidation on the mating conductive surfaces. Do not waste time money or diagnosis time with them. They are good for flushing out old dieelectric grease, and nothing more.

[TrainChaser]

It's ALL magic to me!

Maybe when it warms up a bit, I'll take a look. (I know it's just begging for more trouble, but... )

The ice in the back of the truck melted just enough today that I could go down into the dip in the street (RR tracks used to go there), and slide most of it out over the tailgate. Tomorrow's the only day I can go to the dump, rain predicted for the next ten days.