How to Bench Test Wiper Motor?

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Troub

Troub

67 Dart 270, 225 slant six
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Afternoon!
Since I am pretty weak in all things electrical, I figured I would ask help before blowing up my wiper motor.
I want to bench test it. I have a 12 volt power source. When I took off the car forever ago and labeled the wires and in the pic the wires to the right went to the AC Compressor and Heater respectively. Set on right went to the box in firewall. Not sure why I didn’t label the black and yellow wires in the other pic.
What can I connect to power source to bench test the motor?

DDC64803-43D0-43E5-83F2-23C9223DFDB7.jpeg


9E9F1B99-1DDA-4D43-857E-569E759D6A69.jpeg
 
Wiper motors are not my favorite subject. Run over to MyMopar and download the closest you can get to the proper service manual, free. You may have to accept Dodge vs Plymouth and vice versa
 
@ns1aar is a member who has ben rebuilding those for over 25 years.
He has a post somewhere on the site of how to test it. I will see if I can find it for you.
Home
 
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How to test a 3 speed wiper motor


MOPAR 3 SPEED WIPER MOTOR BENCH TEST



  • High Speed
  • Connect jumper wire from motor case to battery ground
  • Connect second jumper wire from battery positive to BROWN lead
Motor should run on high speed continuously


  • Low Speed
  • Connect jumper wire from motor case to battery ground
  • Connect jumper wire from GREEN wire to batter ground
  • Join the BROWN and RED wires together and connect to battery positive
Motor should run on slow speed continuously

  • Park
  • Connect jumper wire from motor case to battery ground
  • Connect jumper wire from GREEN to BROWN
  • Connect jumper wire from RED to ground
  • Connect jumper from BLUE to positive
Motor should reverse and park
 
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The two wires with terminals probably go on to the other side of the motor in the parking plate
 
Dana67Dart said:
The two wires with terminals probably go on to the other side of the motor in the parking plate
Click to expand...
Well, bench tested and that motor is no good. So now to it’s either send off for a rebuild or source a good one.
Booooo.
 
What motor is it? and what is it out of ?
 
Dana67Dart said:
How did you test it?

The FSM has a test procedure
Click to expand...
Put a jumper from case ground to battery ground. Put a jumper from brown wire lead to battery positive.
Got plenty of sparking when I put the battery positive to the brown lead but no motor movement.
 
If you carefully take off the parking plate you can remove the gear. You should be able to rotate the motor by hand.

Screenshot_20240622-223354.png
 
Thanks Dana. I tried testing just now with that set of instructions. Nada.
I will remove the switch plate and see if I can rotate it by hand.
 
Got to be some brushes and an armature if you can get in to them. See if you can clean up that armature (to shinny copper) and see if there is anything left of the brushes too.

Can probably replace the the brushes if you ultimately have to.

Most basic make sure the brass bushings (bearings) on the armature are not stuck keeping it from spinning. They can be cleaned and re-greased too.

Also check to see the plastic gears are meshing properly, they could be stripped and jambed.


Kind of like cleaning up and old GM starter. Used to do it all the time:

Clean and polish armature Contacts.

Replace Brushes

Lube or replace brass bushing bearings.


☆☆☆☆☆
 
George Jets said:
Got to be some brushes and an armature if you can get in to them. See if you can clean up that armature (to shinny copper) and see if there is anything left of the brushes too.

Can probably replace the the brushes if you ultimately have to.

Most basic make sure the brass bushings (bearings) on the armature are not stuck keeping it from spinning. They can be cleaned and re-greased too.

Also check to see the plastic gears are meshing properly, they could be stripped and jambed.


Kind of like cleaning up and old GM starter. Used to do it all the time:

Clean and polish armature Contacts.

Replace Brushes

Lube or replace brass bushing bearings.


☆☆☆☆☆
Click to expand...
I may try and give that a go.
 
Troub said:
Afternoon!
Since I am pretty weak in all things electrical, I figured I would ask help before blowing up my wiper motor.
I want to bench test it. I have a 12 volt power source. When I took off the car forever ago and labeled the wires and in the pic the wires to the right went to the AC Compressor and Heater respectively. Set on right went to the box in firewall. Not sure why I didn’t label the black and yellow wires in the other pic.
What can I connect to power source to bench test the motor?

View attachment 1716263354

View attachment 1716263355
Click to expand...
I wrote a rather detailed 'How To' article on the forum about two years ago on how to rebuild a wiper motor. It included details about bench testing. It was an easy rebuild. I could not tell from the pictures what WW motor you have. Take a look at the article. It might help.
Rebuilding a 2 speed wiper motor (69 Barracuda)
 
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It’s an early 67 I think as it has the white plastic switch. Guessing a two speed but I know some folks call two speed a “variable” speed, don’t think it’s a three speed.

48C1AC23-785B-4730-A5ED-833AC2673BE7.jpeg


D9B13EA2-0B6E-4EE8-A08A-E82D5C82E128.jpeg
 
Troub said:
It’s an early 67 I think as it has the white plastic switch. Guessing a two speed but I know some folks call two speed a “variable” speed, don’t think it’s a three speed.

View attachment 1716266455

View attachment 1716266456
Click to expand...
Yes. That is the info you need.
It is not like the others and I can not vouch for it being used with the variable switch. I beleive it is a 2 speed by Neville Leece, and I *think* the wiring functions the same as the other two speed used in '67

The date code is probably the 4 digits after the stamped part number.
1719173639459.png


so 3326 is 332 day of 1966.
www.forabodiesonly.com

Wiper Motor Wires

The wiper switch...............It has two distinct clicks but then rotates quite a bit more after the second click, almost another 90 degrees. There s a 2771378 stamped on the side. I believe this is a variable wiper switch? That number is the variable 3 speed switch. Just to add a little more...
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1719173738731.png


There is not black and red wire so the shop manual instruction above is not the right one.

Lets see if we can figure this out.
Dana has been through the switch in detail.
www.forabodiesonly.com

67 2 Speed Wiper Switch Demystified

Some time back I was disassembling and cleaning the switches from my 67 Dart Convertible #2. All went well till I got to the wiper switch. Switch number 2820525, 2 speed with the resister on the back I successfully got the switch open without breaking anything, always a good thing, which...
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www.forabodiesonly.com

2822963 wiper motor 2 speed park bench test

I am looking for a wiper motor bench test that covers the park circuit. I have a 2822963 2 speed, 3 wire wiper motor out of a 67 GTX that doesn't park. I know these motors made it into A bodies as well. Not to waste anyone's time I can confirm the following. - This test is not covered in the...
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I think the Blue is the Park function and that's why its hot when the switch is off.
If so, then the switch plate breaks contact when the wipers are near the bottom of the windshield.

Then Brown is full system power (High)
Red is reduced system power (Low)

Work in Progress
1719177823340.png


This says A to F always connected, but sortof a complicated way of explaining power gets connected to A & F when the switch is on.
1719177884582.png

B/U is back up lamps so they are always hot with the key in run or acces.

This guy agrees and explains it better
www.forabodiesonly.com

Testing a wiper motor

How can I test a 3 speed wiper motor before I go through the trouble of replacing my two speed wiper motor. Thanks,Jim
www.forabodiesonly.com www.forabodiesonly.com
 
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High is not correct way to describe what the Brown wire from A does.
edit. did a little reading.
The shunt field is in the motor means power is need to both the stator (fixed windings) and the armature (spinning windings) .

So bench testing the motor requires power to the16 gage brown wire and power to the 18 gage red wire, plus a ground.
 
I may be wrong but...

The motor does not get power to park.

The power on the park cir gets broken every revolution.

When the switch is in low or high the power supplied there overrides the park cir.

When the switch is then turned off, the park cir still has power and runs the motor till the park plate switch opens. Then the motor comes to a stop. If the windshield is dry the blades will stop higher then if it is wet.

I believe but am not 100 percent sure, that the voltage / current is reduced by the resister on the 2 speed switch. Rather than or in addition to using alternate coils
 
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