I found several good trouble-shooting write-ups and video (Willcox) on testing wiper motors but since mine was all apart and never worked 100% in the first place
Just for the next poor fellow who's wiper motor is totally apart.

This was on my 72, not 100% sure it's the correct motor/pump, might be off a Mack truck or something. (Still looking for a barrel connector pump)


Back off the linear adjusting screw to get it out of the way







Check and make sure the wires are joined securely, I added a small heat-shrink here for added strength



Grease the inside bearing where the worn shaft goes through with a light grease (white grease works will)



Feed the two wires out of the hole and keep pulling them through as you slide the armature into place.



Careful not to pinch the wires.
Align the two long screws and lightly snug them



Now is a good time to test the motor JIC
Ground the case and touch 12+ to the black wire with the pink stripe will spin the motor.
If the armature spins slow, try tapping it with a small rubber mallet to help align the bearing.
If it doesn't spin at all, carefully try to turn the armature with a pair of needle nose pliers. If it spins, pull the armature back apart and check the brushes, bad connections, etc. Wash everything with some contact cleaner and try again. You may have a burnt out set of windings

When it's working, slide on the rubber seal keeping the wires pulled out snug



Grease and drop in the main gear. There should be a thin spacer washer between the gear and the housing



Grease in inside of the bushings and put some extra in the cavity between them




Run a light coat of grease over the outside of the gear and the worm



Run the motor for a minute and bring in the adjuster screw until it light loads the worm, you'll actually hear the motor smooth out, if you run it in too far it will slow again. Tighten the lock nut




The center shaft is in three pieces, the shaft, follower cam and stop cam. They stack together with the shoulder on the stop-cam locating the follower cam into the arm on the shaft




Make sure the three parts are stacked and sitting down together properly (the middle lever has the large hole that must be centered on the pin from the bottom one)



Turning everything over, there is a plate with another thin washer



Washer goes against the housing, then the plate aligns with the two arcs




The plate had a shoulder sticking out around the shaft hole, that goes to the outside (away from the housing)
Now comes a spacer (looks like bronze) and a c-clip



Mine also had a thin steel washer between the spacer and the plate, no mention of this in the manuals.

The black wire with the pink stripe goes over to the tab on the underside of the stop relay



The solid black wire goes to the end of the 1-2-3 plug



The small red wires both go over to the stop relay and attach to the electro-magnet.

I need to find a new connector, there should be a resistance coil/wire along the back there but I've yet to find one intact for reference.
According to Willcox Corvette, the resistance of the missing bit is approx -20.6 ohm, I don't know the total resistance in the circuit so it's hard to say the wattage that would be required




Now you can run the tests as found on Willcox's videos.




Now for the Pump



Shove the piston in with your thumb and slip the pump into the housing. The pump body has two slots that line up with the housing



The little tab on the link has to face up



Now's a good a time as any to install the pawl



There are two little alignment pins on either side of the screw to locate it correctly.

Put a drop of grease inside the gear and drop it in place, you need to push the piston in again to move that tab out of the way so the gear drops on fully, also watch for the pawls not to be in the way



Flip it over and drop the cam wheel onto the shaft and install the locking washer. I use a small socket to press it into place



Put the electromagnet in and use a large screwdriver to spread the tangs locking it firmly in



The ratchet arm can go on, notice in the background the arm for the electromagnet arm riding on the plastic gear



The orientation of the spring for that arm (diagonal) holds it down on the cam track of the gear



An E-Clip holds the ratchet arm on and a spring holds the plastic gear in place



With the motor in the parked position, turn the cam wheel so the pin on the motor locates in the curved slot (greased in this picture)



and put the two parts together and bolt everything up.

When the motor is turning, the ratchet arm is always moving back and forth with the cam wheel but it's not ratcheting the gear ahead, when the washer button is pressed, the electromagnet moves the other arm up and allows the ratchet arm to engage the gear to start turning, the ratchet arm then pulls it around and pumps the pump.
When it makes one full turn the magnet arm drops back into the off spot and it stops the ratchet arm from engaging the gear again.

Anyway, since mine was all torn apart with the wires not connected, and the few images I found were not great, I worked my way through it and came up with this.

Hopefully it comes in handy for someone else.

 

Damn Nice write up Mooser...

 

Very nice!

 

That took a lot of work. Excellent job but you left off your address of where to send you my wiper motor.

 

Hi Mooser ,

Brilliant how did you know i was looking for a write up to fix the wiper motor and washer pump ???

Seriously , a well laid out instruction with pictures , going to tackle my problem a lot easier now : Thanks

John

 

One side of the resistor goes to the back wire on the connector. But where does the other end go? There seems to be no soldering on the other end. So is it clipped or screwed to something? The casing ?

 

by the way thanks for posting the article it has been very helpful for me!

 

Seems to have been a spring wire that grounds to the casing under the relay

Check this thread
http://forums.corvetteforum.com/c3-t...onnection.html


Strange part is when you figure the wattage rating needed, hardly seems that would be a good enough contact...

M

 

Thanks for the quick reaction. But does it go trough the gap and lie lose in hope to make connection somewhere? See picture

 

Or does it go around the terminal and is clammed by the plastic? See pic

 

The remnants of mine were wrapped around the casting post and clamped (when assembled) by the plastic body as you show.

But mine was a basket case so nothing guaranteed
M

 

And my resistor has broken in two, but the wire is still in one piece. Is it still usable ? Can I glue it together? Or can I better use a modern type resistor from 20.6 Ohm 7 watts?

 

If the wire is still conducting through and the ceramic core is snapped (you could try crazy glue, not sure if it will take the heat) you should be fine. In all reality it will work without the resistor at all (mine is missing completely)
M

 

I have tested my motor apart from everything (plain motor). Connected a ground and put 12 volts to the black red wire and it did run like hell. So that's not the problem. I put the hole thing back together and put it back in the car after checking the ground wire connect to a good ground.
But it does not work, what can be the problem?
Can it be the relay under need the green plastic? If it is can i find a new one, and where?

Which voltages should be on the green, yellow, and blue wire on the connector so i can messure them in the car?

 

Depends on what year your car is, there were several different version

Check Willcox site for several excellent testing videos
M

 

I checked my motor as on the willcox video and it works as disigned. I have installed a brand new wiper switch. I checked my ground and checked my wiperfuse in the fuse box. They are all OK.

I checked the voltage on the red wire which goes to the wiper motor. I believe there should be 12 volts on the wire when the wiper door is open but there isn't. What can be the problem?

 

OK so I'll take it the car is 68-72 then
Tracing backwards, do you have 12v going into the switch on the wiper door?
M

 

At last I found it.

I checked my wiper door switch with my multimeter on diode setting. So when I pushed the button it sayed beeeeb. When I let it go it was slilent, so you think it's OK.

But there was 12 volt going in but not comming out.

So it took it apart and cleaned it. Put it back together and it worked.

So the switch was working but probably the contact was not good enough to let the current flow. Strange but it works now. Yippy!!

Thanks mooser for al your help!

 

Adding to an old old thread
If the internal resistor is broken, it is possible to sneak a more commonly available ceramic resistor into the area beneath the connectors and ground it to the case

Mine was broken and the last time I had it out to remove the washer pump assembly (went electric) I replaced it with this one, works as it should
M