Early Wiper Motor Park Function

[DomSmith]

I decided to pull the wiper motors from the 65 SWB to see if I could get the park function to work as they currently stop wherever they are when you turn the wiper switch off. The first thing I did was pull a spare from the parts bin and remove the rubber cover. This one is in pretty good shape considering. It sure would be nice if someone like racer would reproduce these...

Next I hooked it up with long jumper wires (to the drivers side wiper motor) as a third wiper motor to see if it would park...

The wires are as follows:

Top wire (Blue with white stripe) = Switched power (12v when the switch is on). Mine is connected to battery power and did not need the key on.
Middle wire (White with black stripe) = Ground
Bottom wire (Blue)= 12v hot all the time

Luckily it worked like a charm. The other motors stopped when I turned off the switch but this one kept going and then stopped. So I took a closer look to confirm the park function operation and parts involved....

The parts are:

Plunger/pin
Copper plates with contact
Switched wire contact point

Here's the plunger pin on the inside of the motor. It is spring loaded and drops back towards the cam until it is pushed out towards the copper contact plates...

This is the plunger on the outside of the motor that the pin pushes into the copper plates.....

You can see on the example above that the plates are bent and don't rest up against the plunger like they should.

 

[DomSmith]

These are the copper plates that are bolted to the motor and flex as the plunger moves back and forth which in turn contacts or breaks the contact with the top (switched) post. On the underside is the contact point...

One of my wipers had a bent copper plate. All it took was bending the plate into position to get it to work properly. I chose to exaggerate the bend to be sure the contact was made. When I initially bent it back to straight it didn't hit the contact point so I opted for an excessive bend. This may be due to a worn plunger?


Original bend in the plate. The bend was angled away from the contact point...

This is the plate bent towards the contact plate...

I cleaned up the contact points and put it all back together and this one worked!

The rubber grommet that holds the motor away from the windshield disintegrated as soon as I pulled the motor so I used a small o-ring as a temporary bushing until I can source something closer to original.

I think the rubber washer on the outside of the windshield that the wiper shaft retaining nut holds on will work but I need to see if they are available anymore.

 

[whitey45]

Nice tech Dom, going to check mine, nice fix if it’s just a matter of bending the plate back! Thanks for sharing!

 

[DomSmith]

I next turned my attention to the passenger side wiper. When the switch was turned on and the motor ran the plunger did not move.

Once pulled apart I could see that there was quite a bit of the goopy grease stuck to the cam on the inside. This was too much for the spring to overcome so it was stuck in the "out" position. A quick removal of the grease and exercising the spring and it was back in business. It returned to the normal position when the internal cam moved off it and pushed out towards the contacts when engaged by the cam.

This is the cam that pushes the plunger pin as it rotates...

This is the rubber grommet I mentioned on the initial post...

This is the drivers side sun visor I broke during the process. (Please see wanted ad in the 45 classifieds)...

 

[DomSmith]

Now both wipers park to the right of the windshield no matter where I shut off the switch or how out of whack they are from each other!

I'll try to post a video.

 

[DomSmith]

Nice tech Dom, going to check mine, nice fix if it’s just a matter of bending the plate back! Thanks for sharing!

Brian-

I'd say take a look at the plunger when you turn on the switch and you will probably see no contact being made. There is a small nut on the backside of the screw that holds the copper plates in place. Definitely need to remove the motor from the windshield and take care when getting the screw out to bend the plate.

Hope it's a simple fix like mine!

 

[seth]

I next turned my attention to the passenger side wiper. When the switch was turned on and the motor ran the plunger did not move.

Once pulled apart I could see that there was quite a bit of the goopy grease stuck to the cam on the inside. This was too much for the spring to overcome so it was stuck in the "out" position. A quick removal of the grease and exercising the spring and it was back in business. It returned to the normal position when the internal cam moved off it and pushed out towards the contacts when engaged by the cam.

This is the cam that pushes the plunger pin as it rotates...

View attachment 1925798


This is the rubber grommet I mentioned on the initial post...

View attachment 1925799


This is the drivers side sun visor I broke during the process. (Please see wanted ad in the 45 classifieds)...




View attachment 1925800

I’ve got the driver’s side in pretty bad shape!

 

[seth]

If you need it, @DomSmith , send me a PM

 

[pardion]

Good job Dom.

 

[middlecalf]

Wow, no JB Weld anywhere inside those wiper motors. Nice! Mine on the other hand...

 

[DomSmith]

I added the wire colors to the initial post.

Also: when the plunger is pushed out and breaks the contact to the top (switch) wire that is when the wipers will park. So if you turn off the switch while the plunger is retracted (at rest) the wipers continue until the cam pushes the plunger out against the plates and breaks the contact and stops. This leaves the wipers to the far right of their stroke.

 

[pardion]

@Bear are you following this thread?

 

[Bear]

John,

Here's my rather long take on the early wipers:

I have seen this thread and read as many others as I can find. Unfortunately, heavily used and abused motors are not as easily remedied, such as some, not all, I have come across. The copper reed switches do need adjustment, but I have found they are only one of a number of problem areas. The sad truth is that these were not designed to run and last forever, and there are a number of wear points such as the cam on the large metal gear, the friction pad on the motor side, metal-on-metal rotations without bushings or renewed lubrication, the rotor post, and so on. The TNK company simply globbed-on a thick wad of grease and that was it for the past 50 years of running (or not.)

Other than the obvious lack of cleaning and re-lubing, like you, I have opened some where parts have "disappeared", rust has completely eaten into and overtaken the commutators, the hair-thin wires have been broken, the motor has shorted-out due to a bashed in aluminum case, and many badly bent shafts with butchered tips; motor brushes worn down to the nub. For the lucky owner with motors that haven't been abused, restoration is very possible, but each case is different, and as you know, parts are non-existent and probably always were. I suppose that's why "in the good old days" it was easier to simply buy a new one and bolt it in. Such is not the case today, and we're left with trying to bring these old things back to life.

I have a sneaking suspicion that the reason the few motors that come up for sale are available, is that they were removed due to non-operation long ago, and kept around as a back-up for a "future" repair that never happened. And saddest of all, of course, is that even in their prime, they never synchronized with each other, and had a hard time keeping up with serious rain--hence the later style motor at the bottom of the windscreen--tied together with a linkage--which themselves have been modernized on later vehicles. To drive a Model T, whether a Ford or a Toyota, will always remain an acquired taste--bumpy, lumpy, slow, leaky, cranky, somewhat uncomfortable, and lacking in any of the comforts we have become accustomed to nowadays. And if the wiper or wipers actually work, bravo, since it sure beats sticking your hand out the window with a wipe-rag !!

Congrats to Dom and others who have successfully brought their motors back to life--you can thank the Previous Owner for their care, however minor that may have been. Meanwhile, some of us will be cursing at the folks from our "throw-away/use-and-replace" generation--as is the case with the shrinking availability of decent condition old "stuff" in general.

Anyway, my personal opinion, likely worth something less than 2 cents.

 

[pardion]

Truth is in the pudding.

 

[Bear]

And the crowd said, "Amen."

 

[pardion]

Maybe TNK bought stock in "Rain Ex"?

 

[Bear]

I'm note certain, but is TNK also called Tanaka, the fabulous air-bag manufacturer? If so, they have enough problems without worrying about windshield wipers !

 

[middlecalf]

I just wish there was an equal supply of unused early wiper arms that were once mounted on all those non-working wiper motors. Maybe they’re all sitting on old VWs, I have one VW arm on my ‘65 40.

 

[cult45]

Will a R/T windscreen frame fit a fixed cab? One potential wiper solution there.

 

[Marn0]

I do recall somewhere on the interwebs seeing an aftermarket wiper motor that looked almost an exact replica for those motors but as usual im buggered if i can remember where!!