beerme

Hi all,

I have an interesting problem and I don't know how to fix it so I am asking for your help.

Please note, I HAVE REPLACED THE WIPER MOTOR and the problem persist.

My wiper motor is actually spinning inside the wiper arm mount. I thought okay I have an old mount and old wiper motor so I will replace both and eliminate the issue from years of torque rounding the interior corners of the wiper arm mount (or so I thought).

New wiper motor, new wiper are mount and exact same thing, the wiper arm spins inside the mount. I am at a loss as why this is happening versus the wipers arms actually moving across the windshield as they are suppose too.

Has anyone seen or experienced this behavior and if so can you please point me in the right direction for repair? I don't want to take to shop as I like fixing these things myself, just not sure where to look on this one.

Thanks in advance for any and all insight....

aDigitalPhantom

Can you record a video of this happening?

With what is here I have no idea what is happening.

beerme

I will see if I can get a video together, but let me explain a little better (I hope).

The main shaft of the wiper motor which goes thru the firewall and connects to the wiper transmission arm mount is the problem.

The wiper transmission arm mount has a keyed slot which fits onto the wiper motor shaft. The wiper motor shaft spins inside of this mount instead of rotating the mount in a circular motion which would move the wiper arms across the windshield.

As I type this I am starting to wonder if this is a symptom and not the problem, rather the problem is elsewhere in the wiper transmission arms, perhaps binding or something.

Just very lost on this one....

Thanks again,

WVZR-1

So the motor spins inside of the "crank arm"? You used a different motor but used the same "crank-arm"? OR does the crank-arm turn also but the link to the wiper transmission doesn't move. I'd sooner think it's a failure of maybe the connector at the transmission to the crank-arm .

I would concentrate on likely a failure of the left side transmission.

maddogwyatt

Thanks in advance for any and all insight....

[/QUOTE]

I don't know if this is relevant, because I've not even looked at the wiper system on my Vette yet, BUT my daily driver suffered from wipers that got slower, and slower, till it was ridiculous. When I looked the motor was trying to twist itself free of its mount. I disconnected the linkage from the motor and discovered the wipers were nearly solid. Turns out that the shaft of one wiper had expanded with rust so much that it was nearly seized inside the female part. I drifted it out with a hammer, filed all the rust off, and put it back together with plenty of grease - Fixed for free!! Worth checking?

beerme

Yes, both the wiper motor and crank arm were replaced due to this problem and it is still occurring.

Yes the motor spins inside the crank arm, when I have the crank arm loose I did move the wiper transmission arms and they seemed free of binding but I am starting to wonder if they are binding on something.

I have tightened the nut on the wiper motor pretty tight, in fact I am afraid I am close to stripping the threads if I torque it much more, and the wiper motor itself is secured to the firewall and isn't moving.

Thanks again for all the insight....

ovrebo1

Bump, I'm having the same problem

beerme

I didn't find a cure for it yet, not sure what to do about it. But I can say I usually don't drive the car in rain, however you never know when mother nature may decide she needs to pee on your car.

I am hoping someone who has had this problem sees the thread and can definitively say this is the problem and here is the fix.

Thanks again,

ghoastrider1

That wiper motor arm fits into/onto a square output shaft from the tranny. Rather the shaft is round but has a square end on it the arm must fit onto. The arm has a square punched out hole that fits the shaft. A male and female sorta thing. Be sure the hood isn't pressing down on the wiper arms/blades themselves which is so common with the lousey replacement out there. Also make sure the arm isn't behind the wiper arm stop block where its supposed to be at "park" . If I have time in the morning I will post a pic and you can tells us where the problem is.

Nicksvette

Had a Similar problem on my vette when I first got it, sometimes the tranny rod connections that go from the little motor assembly to the wiper it self gets loosened or completely disconnected, if that's not the case, maybe the wiper arms themselves are stripped, sorry if you already tackled this, I wrote this late at night and was tired, apart from those two ideas, I'd have to see some pictures or a video to get an idea of what you're talking about.

beerme

[QUOTE=ghoastrider1;1589679068] Be sure the hood isn't pressing down on the wiper arms/blades themselves which is so common with the lousey replacement out there. Also make sure the arm isn't behind the wiper arm stop block where its supposed to be at "park" QUOTE]

I will have to take some pics I guess, but this happens with the hood up and the wipers not locked in the park position.

Basically the wiper motor spins inside the crank arm.

In my case both the wiper motor and crank arm are new, same behavior as original equipment I replaced. Which tells me I have a different problem just not sure where it is, yet anyway.

Thanks again....

ovrebo1

My wipers aren't parked or obstructed by anything. As a matter of fact they are in the slightly up, ready to sweep position and then they just sit there and dance around like Michael J Fox while the motor spins in the arm.

I have an extra motor with that arm on it. I'll have to loosen that bolt and take the arm off to see what could possibly cause it to not stay keyed into its slot.

Nicksvette

Just wanting to see for an update to see if you guys have found your solution, if not I'd be glad to go through mine and show you the working connected parts with pictures/videos.

aDigitalPhantom

I don't know how much the wiper system changed over the years. So this may not apply.

On my 93 the crank arm has what I would call a DD shaped slot to connect to the motor. All of the aftermarket "wiper transmissions" I have seen use a round hole that is supposed to "press" onto a splined wiper motor.

It sounds like you need the correct crank arm, and maybe a new wiper motor. However without seeing it I cant say for sure.

ovrebo1

Sorry, I saw my extra one yesterday and it crossed my mind to take it apart, but I didn't

suicidejockey

I'm having a similar problem with mine. I replaced the wiper motor cover because all the other wiper threads I've seen said start there. The problem remains. When you first turn on the wipers, they only jump up and down a few inches, and you have to put the switch on hi-speed to get that much action. After a few minutes of this, then they start acting normally, but only on hi-speed. I changed the cover yesterday and was standing outside the car testing it when I looked inside the cowl and noticed that the shaft that goes between the motor shaft that comes through the firewall and the rest of the transmission seemed to be getting stuck. I pushed down on the transmission end of the shaft and the wipers started acting normally. I'm guessing that joint is worn out. I'm going to pull it apart on Sunday. I'll let you know what I find. BTW, my car is an '87.
Bob

ovrebo1

Thought I would update this, even though what I'm about to say isn't a lot of help

I took my extra one apart and sure enough as someone mentioned, its like a D shape key way. So the only reason I could think of as to why it would spin is the motor has manged to spin in the key way and its now stripped