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Square body wiper systems SUCK! Can it be fixed?

This is what the link that blazer 74 posted has to say about the wiper motor ground strap.

"Since the motor is mounted on rubber cushions, it's grounded via a copper strap attached under one of the mounting screws. This is the ground for the park switch. "
 
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That may be true for the 70's systems, but on the 80's systems, the park switch uses the two smaller wires shown in the picture above. It's isolated from the wiper case otherwise. It's not uncommon to see ground straps like that for EMI purposes. I don't know if any DC current actually returns through the case.
 
It's just like a ground on a drill most likely. Theoretically power will never short to the case. But if it does, the ground is there to provide a circuit allowing the fuse to do it's job.

Instead of the case just sitting there powered up
 
Those are two completely different scenarios. Unfortunately, "ground" has so many different meanings.
 
They're identical scenarios. Going by the wiring diagram above. The case is not used for the normal ground path or operation. So If that's the case it is exactly like the drill.

Not saying that's it. But ts a possibility, and the scenarios are the same.

If it shorted internally it would look for a path to ground. Not finding a good one, with the rubber feet and all, it would start arcing in the gears, linkage joints, pivot point, etc. And it could do a lot of arcing/damage before it pulled enough amps to take out the fuse.

For the drill it would do it to protect you not the equipment. But the concept I'm theorizing is the same.
 
The green wire in the drill is a safety path, to protect people from getting 110VAC their body. No such danger exists in a 12V system. The strap on the wiper motor is prevent electromagnetic interference. Essentially it helps keep wiper noise out of your AM radio. At radio frequencies, the impedance of a wire increases to where it's not effective enough anymore. The shape of the strap has inherently lower inductance.

I haven't measured if the return wire pictured above is even tied to the case.

As frequencies, voltages and currents increase, a wiring diagram/schematic tells less and less of the story, while the limitations of the materials and parasitic effects do more.
 
Every square I've owned had crappy, weak wipers.
There has to be a stronger motor or something that mounts similar. I just haven't actually ever tried to find one yet


Same. Lame as Fok :surepal:
 
12v system doesn't have the danger of killing you, but it has a very real danger of burning your car down.

I can see is being a case bond for interference though.
 
Where the column bolts to the dash, you will find an aluminum finned box that plugs into the wiper wiring. It can be removed and the two cable assembly's can be directly plugged together. If no box in series, them no variable speed wipers. The stalk should show delay on it also.

I finally got around to checking this out today. I do have that silver heat sink type box in place.

The control stalk does have multiple positions as if multiple speeds, however only one speed works.

Need more time to start tracing wires and stuff.
 
Quick check is to remove the delay module and plug the wiring harness together. This will tell if it is the module or the switch. If that does nothing next is the motor.
 
Something to consider.....
Way longer than I care to think about, I was in a marine parts store, and saw a Dutton/Lansing electric Anchor winch. Not sure what kind of boat it was designed for, since it was fairly small.
I was doing a lot of fishing for channel catfish in the big river on weekends. Between the current, water depth, and nonfouling anchors, we often had to throw out 60 or 70 feet of anchor line to hold the boat.
Hauling that much line in when we wanted to move got old after a while.
I installed that winch on my small skiff, and it was wonderful. Which meant that my father and all my friends wanted one.
But, they had discontinued them.
This was before the big bass boat craze. Nowadays, electric anchor winches for freshwater boats are available lots of places.
I found a different brand of winch, that mounted differently. It worked, but did not have much power. In looking at it, I realized it used a windshield wiper motor with a simple gear reduction.
I knew a guy who owned a NAPA store. We started digging through his stock of motors. We found a couple that were much stronger than regular motors. At this late date, I have no idea what the model numbers were or what they fit.
But they would wind up 100 feet of anchor cable with no problem direct drive.
Naturally they would not mount to a stock setup, but the winch mount I designed and built was anything but a stock usage. I would look at motors for large windshield vehicles, like semi trucks or buses. A motor designed to swing a 24 inch wiper has to be more ballsy than one to swing 16 inches.
Just make sure they are 12 volt and not 24.
Find a super strong motor, fab a mount and shaft coupling, and you're in business.
 
Just an update. I went on Rockauto, found some large trucks that used 24 inch wiper blades. But they did not list motors. did a search for 24 inch blades, found some Chevy vehicles use them in the last few years.
Finally found some limited listings. For instance the 2018 Impala. But that motor is out of stock.
Found it on amazon.
https://www.amazon.com/ACDelco-20980563-Original-Equipment-Windshield/dp/B007Q1C4J6
Don't know enough to suggest buying it and trying it, but it sure looks stronger than the stock ones.

And, if you get bored one evening, here is all you ever wanted to know about wiper systems. Just came across this.

http://www.imtra.com/Collateral/Documents/English-US/Wiper_Brochure.pdf
 
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well ill chime in..

first I did a quick autozone search for 19787 k20 wiper...

Notes: Conventional design
Fits driver side or passenger side. 16" wiper blade


my truck has been in my possession since 1988 and I have done so many body swaps, front clips, etc.. I have no clue what I have.. BUT..
my wiper has always sucked. Sucked when I had my 78 cab.. sucked when I had my 8something cab and still suck with my current 82 c10 cab...

what is really interesting is reading all 4 pages and seeing pics.. like the one back a page. The motor shows a connector up top, down low and bottom. Then yous guys are talking about park ground, high low ground etc...

I put a 1991 fullsize Jimmy column in my truck (when I took the hydro clutch stuff as well) and now I have high beams and wipers on column. In addition to high/low on column. I have always had high/low and squirters when you pushed that old slide switch in...
Now I think about it.. I think have delay wipers and am going to have to check tonight.
(re-editing.. no I believe the wipers on column gave me "Mist" not delay..)

I do know that if my windshield is DRY, the wipers barely and I mean barely move.... if they are wet.. they kinda go so I agree with everyone that it would be nice to have them like todays trucks.

I will go and grease up my knobbs..errrr. I mean pivot points, etc.. as well... hah..

I just got my truck adjusted by a guy that came over last night and she is running great. next is fix my steering wandering issue (I know what it is as I need a new gearbox)... then this summer I want to get my wipers going better as I too have mud issues...




here is my wiper motor and I only have 2 plugs..
large pic ==> http://www.supermotors.net/registry/media/219646_1

dscf0035.jpg



I couldn't see well due to the mud I was roosting 20ft in the air.. LOL... man was it pouring mud...
unhappy4thmuddin-(4-of-4).jpg
 
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I'm sorry the what? What other wiper arms (that fold fwd) fit the 81 up square wiper trans?

Thanks!!!

I didn't buy them, but when I was walking through the junkyard I snagged a set of wiper arms from a 90s pickup truck, and successfully fitted them to an 80s square pickup. And then I bought the arms from the square (with the squirters). I now wish I had bought the other ones. :rolleyes:

I could probably have bought them both and just swapped the spray nozzles over, but I didn't try that combination.
 
Agreed the washers on the arm of my 91 Blazer blow the cowl mounted ones on my 84 away.
Just wish I knew the exact year interchange of the folding wiper arms. Wonder of Van arms might work ?
 
The wipers on my M1008 have always been mediocre... Until the slow speed wiper position quit working. Now it's fast or nothing. I traced the problem to the wiper switch on the stalk, but I haven't gotten around to tearing the steering column apart. Has anyone had experience with that? Rock Auto or LMC had the switch last time I checked
 
Most of the problem is the geometry, but the 91s do have a better motor. I was considering doing a motor swap. 15 in blade refills are getting hard to come by, Napa makes the best. I agree with the relay/wire setup afterwards.
 
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