2012 Ford Explorer rear wiper arm install issue

[Whapack]

Hi. The rear wiper arm has cracked and completely broken off. I bought a new wiper arm and cannot install it because there's a metal unit exposed. See photos attached. Is this metal unit came from the old wiper arm or from the shaft? I already sprayed wd40 to try to remove it but no luck. How can I remove this so I can install the new wiper arm. I dont want to damage the metal unit if that's from the shaft

Thanks in advance

 

[peterk9]

Does the new arm seem to have a similarly grooved part in it? Can't tell from looking at the top.
Have a look t this video. It is for the 2013-2019 and is a little different than yours so I don't know if the cleaning method will work or if it is an altogether different assembly.
If that part was removed, is there anything in the new arm that would lock it onto the old threaded stem?

Peter

 

[Whapack]

Does the new arm seem to have a similarly grooved part in it? Can't tell from looking at the top.
Have a look t this video. It is for the 2013-2019 and is a little different than yours so I don't know if the cleaning method will work or if it is an altogether different assembly.
If that part was removed, is there anything in the new arm that would lock it onto the old threaded stem?

Peter

Hi Peter,

This is the new one. It doesnt have grooved part in it

 

[Whapack]

Hi Peter,

This is the new one. It doesnt have grooved part in it

View attachment 426457

I found the old broken arm. It looks like the old one has a grooved part in it. So is it safe to cut this metal using a dremel? I was not sure if this metal was the part of the wiper shaft

 

[peterk9]

I'm just wondering how the arm attaches to the threaded stem of the motor. There has to be something to grip onto. It is hard to tell from the pictures but it seems that the hold in the old arm is larger than the new one. Does it look like that metal insert might pop out?

Peter

 

[Whapack]

I'm just wondering how the arm attaches to the threaded stem of the motor. There has to be something to grip onto. It is hard to tell from the pictures but it seems that the hold in the old arm is larger than the new one. Does it look like that metal insert might pop out?

Peter

Thats what Im not sure about . I could not remove the metal insert, it's too tight. I even sprayed it with wd40. I want to make sure before I cut it that the metal insert is not from the stem of the motor

 

[JAPeterson]

It is a different year but I doubt that they have changed that much over the years. This video is for 2006-2010 years.




It just shows a round hole in the new wiper arm. You could always compare part numbers over the years.

 

[peterk9]

It is a different year but I doubt that they have changed that much over the years. This video is for 2006-2010 years.

It just shows a round hole in the new wiper arm. You could always compare part numbers over the years.

Once the arm is removed, it looks a lot like the video for the 2013-2019. There is just a small grooved collar that the arm engages. It's that corroded mess in the OP's first picture that stumps me and what does that new arm grip on?

Peter

 

[JAPeterson]

A lot of times it will be just a tapered fit with the grooved collar built into the arm. The piece still attached to the wiper motor stud looks to be aluminum and over the years I can and will corrode to the point that it looks like what it does in the picture.

However that I where I would compare part numbers over a few years before I go to cutting a piece off, but I am pretty sure that the grooved piece is part of the old arm that broke off.

 

[peterk9]

A lot of times it will be just a tapered fit with the grooved collar built into the arm. The piece still attached to the wiper motor stud looks to be aluminum and over the years I can and will corrode to the point that it looks like what it does in the picture.

However that I where I would compare part numbers over a few years before I go to cutting a piece off, but I am pretty sure that the grooved piece is part of the old arm that broke off.

Even so, the new arm has no grooves to lock onto anything.

 

[JAPeterson]

It doesn't need grooves to lock into anything as far as the hole is concerned, that is where the tapered fit comes into play. There are quite a few industrial applications where there are no grooves in a hole where it mounts but there are grooves in the off side of the hole that are molded into the arm or whatever is going to move.

This prevents a wiper arms such as this from destroying the motor if the arm is stuck. The motor should have enough torque to actually spin inside the mounting hole if something like this happens, but it is secure enough that it will allow the arm to wipe the window even if the wiper is slightly stuck.

One way to see just how the new arm is manufactured would be to destroy one and see if that insert is actually grooved on the outside of it where it is molded into the plastic arm.

 

[Odrapnew]

I believe the grooved part that is on the shaft is an overmolded insert. That part is put into the injection mold and plastic is molded over it.
The grooves (or teeth) are used to keep the metal retained in the plastic and prevent it from spinning inside the plastic.

Looking at Ford parts site, the images on the site also show a metal insert with smooth ID.

https://parts.ford.com/shop/en/us/wiper-and-washer/wiper-and-washer-related-parts/arm-assy-wiper-6364895-1

I agree with JAPeterson that the piece is from the old arm and corroded to the shaft and needs to be removed.
WD40 isn't really a penetrating fluid. Try PB Blaster or something like that. Might need to reapply multiple times over a few days.
Try to grab it with a pliers and GENTLY try to spin it on the shaft. Rock it back and forth and pull outward if you can, but don't force it.
You could also go the dremel method. It appears to be aluminum, so it should be fairly soft and easy to cut.

 

[dfox52]

Hi. The rear wiper arm has cracked and completely broken off. I bought a new wiper arm and cannot install it because there's a metal unit exposed. See photos attached. Is this metal unit came from the old wiper arm or from the shaft? I already sprayed wd40 to try to remove it but no luck. How can I remove this so I can install the new wiper arm. I dont want to damage the metal unit if that's from the shaft

Thanks in advanceView attachment 426452View attachment 426453

This is exactly what happened to me last week. The metal bushing is part of the old wiper and needs to be removed. It is pressed on over a knurled shaft. You can try to pull it off but I doubt you will have any luck. I cut mine off with a dremel. Just be careful not to go too deep and mess up the knurled shaft.

 

[Whapack]

I believe the grooved part that is on the shaft is an overmolded insert. That part is put into the injection mold and plastic is molded over it.
The grooves (or teeth) are used to keep the metal retained in the plastic and prevent it from spinning inside the plastic.

Looking at Ford parts site, the images on the site also show a metal insert with smooth ID.

https://parts.ford.com/shop/en/us/wiper-and-washer/wiper-and-washer-related-parts/arm-assy-wiper-6364895-1

I agree with JAPeterson that the piece is from the old arm and corroded to the shaft and needs to be removed.
WD40 isn't really a penetrating fluid. Try PB Blaster or something like that. Might need to reapply multiple times over a few days.
Try to grab it with a pliers and GENTLY try to spin it on the shaft. Rock it back and forth and pull outward if you can, but don't force it.
You could also go the dremel method. It appears to be aluminum, so it should be fairly soft and easy to cut.

You are right. I was able to cut the grooved piece from the old arm using a dremel. Thanks for your help guys