Was: Odd Problem #587 (Wipers) Now: Thanks for Playing

[Tom Mullane]

Brett and Royal,

You misread Dave's original answer:

"The wiper motor is designed to stop at the same point every time.  If,
in
fact, yours are ALWAYS stopping at this same point (1/3 way up) every
time,
you just need to adjust the arm on the wiper motor."

He is adjusting the arm on the MOTOR, you are thinking WIPER ARM on the
pivot.  (Of course, you may need to remove the assembly to do this, so
you may as well take the motor apart and find out what's going on, as
Brett suggested.)

Tom



At 3:18 PM -0400 6/27/02, Djdawson2 at aol.com wrote:
>--
>[ Picked text/plain from multipart/alternative ]
>Royal,
>Yes, that will solve that problem.  Basically, the wiper motor
regulator arm
>moves like a crankshaft in the engine.  Your wiper motor is stopping
(when
>you turn it off), but the arm is not at BDC, so to speak.

If the arm is not properly adjusted, why does it reach all the way to
the bottom of the windshield during "on" operation, according to
Paul's description?

When you switch the wipers off, the only thing that powers the motor
to get the wiper back to its home position is a set of conductive
tracks inside the wiper mechanism.  There are two such tracks; one
handles the extend, the other handles the retract

There is a break, or some dirt/carbon on the retract track, and when
the wiper tries to return, powered off that track instead of the
wiper switch/relay, it stalls.

The other("extend") track powers the motor in the same direction
until it hits the end of the travel...which is where the "retract"
current track causes the wiper to return back.  The tracks are
probably on a gear which turns once per complete wipe cycle.

If you adjust the arm 1/3rd of the way further counterclockwise,
you'll end up with the wiper blades reaching about 2/3rds of the way
up the windshield and 1/3rd of the way into the $60 rain cover :-)

Brett
--
----
"They that give up essential liberty to obtain temporary
safety deserve neither liberty nor safety." - Ben Franklin
http://www.users.cloud9.net/~brett/
http://www.apple.com/switch/