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MG TD TF 1500 - Wiper motor - polarity?

I got a new old stock LUCAS wiper motor.

Is the right function depending on the polarity? I've seen the gears are diagonally, and I suspect that this will require a certain turn direction of the motor.
W_Mueller

Here is good write up on overhauling a wiper motor found on Totally T Type 2

http://ttypes.org/ttt2/new-life-for-an-old-wiper-motor

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40. Connect wires, in any order. ******

41. Stand back, admire, and test operation.

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Seems it don’t matter which way round you connect the wires.

Rod
Rod Jones

I'm guessing the the bevel cut gears are used to reduce noise
W A Chasser

The motor can run either way depending on polarity. Either way it will cause the wiper's to travel the same way.
J MacDonald

looking at the wiring diagram for the TD. The power would seem to go to the bottom of the two terminals.
Just checked my wiper motor and that is how mine is wired up.
As someone else noted the motor is DC and will run in either direction OK - but if it gets really hot I would try it the other way round.
It does run hot anyway and I believe Lucas do state that.
Only if you can smell the varnish insulation is when I would consider looking as to why.
In England with RHD - I think most MG T drivers have well developed left arms. From operating the wiper by hand.
RainX is also a beautiful thing :)

Rod.
Rod Jones

The wiper unit is intended to run warm but not hot.
J MacDonald

Thank you all

because the polarity seems to be with no matter I'll try the exchange of polarity. After that I'll choose the option with minor noise.
W_Mueller

If the wiper runs hot or very warm, it likely hasn't had the gear case grease changed since it left the factory. Clean out the old waxy grease and replace with a white lithium grease. And while you're at it, send a few drops of light oil down the oilers on the outside. (the two button like brass things on the base). These provide lubrication to the armature shaft bushing.
Lew Palmer

Hi Lew - thank you again for your advice.
W_Mueller

Like the starter motor the wiper motor will only run in one direction regarest of polarity. If you take the cover off and you will see the motor runs the same way even when you reverse the wires on wiper motors termanels. Forrest TDC/22679
Forrest Rubenstein

Forrest you are so right!

In all DC motors the direction of rotation is reversed by reversing either the current direction in the armature winding or the direction of current in the excitation winding. Changing the polarity reverses the current in both windings and the direction will not change.

Shame on me - it's so long ago I'd studied this facts.
W_Mueller

This thread was discussed between 30/04/2017 and 08/05/2017

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