wiper arm stud - spline worn, arm does not hold

[abscate]

S/v70 wiper arm setting

[foggydogg]

One trick I tried - I think Robert suggested it - was to put a passenger side arm on the drivers side. It clears the 850 hood better.
If you can clean up the teeth on the post - and it looks like there is still meat on the bones - try another arm ?
I may have a spare wiper rig floating around, but shipping might be more than a junkyard unit. Replacing it isn't all that bad a job, with the usual cautions about being gentle with the plastic bits. It'll be a good opportunity to clean all the leaves out, and replace the cabin filter (if fitted; If not, get one at the J/Y; 70 series is the same, as I recall .)

[850forum]

Lat night I realized that you have to take the arms off to remove the plastic cowl, in order to remove the mulch that gathers under there & to change the cabin filter.

So how do you heat the loctite to loosen it, without melting the nearby plastic? Torch or heat gun... ? How hot?

EDIT - now that I took it off, I see the ridges on the bottom of the threaded stud.

Don't recall if the wiper arm hole is flanged. It stopped raining & is dried off, so going out now to take it apart & scrape at it...

If I scrape off all the black coating on the flange, I suppose it might rust, but I don't think the aluminum arm would get stuck to the steel flange ?

[850forum]

How do I remove the wiper assembly?
I see it is an assembly with motor, gears, shafts & studs on a long housing.
I see a nut on the driver's side, and then a sideways flange on the firewall that seems to be a pivot point.
Does the pivot have a screw? There is a shallow slot.

There are 2 drains for the top of the cowl.
Underneath, I see a drain in front of the air intake.
But there is a 3" deep puddle around the fuse box assembly (have to use a hose to dislodge all the crud).
How do I get that to drain?
Do I need to lift up the fuse box assembly? - I see 2 nuts, one is somewhat interfered with by the wiper stud "ring."
Can I do this safely without disconnecting the battery etc etc?

[abscate]

Always disconnect negative terminal on battery

I recall two bolts hold in the wiper assembly.

[850forum]

I sucked the water out with a siphon, and I can see part of the drain hole, and there is just enough room to use the "jet" setting on the hose to shoot water into it. Then I poured a solution of Dawn Detergent in it, to soften up any slime sticking to the inside of the tubes. Did that to all of them.

I am going to cut a piece of sponge or cloth & stick it down on the right side of the fuse box, to prevent stuff from getting to the front of the fuse box and clogging the drain.

[850forum]

A dental pick pops out the soft metal pretty well.

However, what I thought was the flange at the bottom of the stud was a cracked plastic piece.
Not sure if it was a washer, or was the top of the plastic "cup" that sticks up.
Anyway, it revealed a snap ring and a metal area with dried grease.

I guess the grease is for the shaft, and not intended to lubricate an actual washer that takes some compression from the arm? I guess I'll put a little grease on it & replace the plastic "washer."

Also finding dried red-oxide gook on the threads. I never used Loctite on this, maybe remains of factory goop?

The passenger side looks very clean, I wonder why the driver's side got all gooked up. Never had problems with the passenger side.

And is there a best method to pry off the arm when you need to get under the cowl? Maybe a nail-puller shaped tool? Use a thin wood block? Levering it straight up seems impossible. Gear puller ?

[850forum]

And the wiper arm hole is smooth, so ordered a new one.
Compaing the the passenger side, the plastic "washer" seems to be the broken-off top of the plastic "cup" that covers the works.

Also, the holes in the cowl for the wipers don't have any gasket to keep water from getting under the cowl.
Maybe I'll put some duct seal around it, just to keep the accumulation of mulch under control.

[850forum]

Geez, $75 for the wiper arm from the dealer. Should have ordered online, since it rained for 3 days anyway & I could not have installed everything in the rain.

Still wondering what the preferred method of prying off an arm is, to avoid damaging anything. Gear puller maybe?

[850forum]

This new blade does not have any serrations in the hole. Are they supposed to be there, or only formed after screwing it on tight ? They gave me PN 9151087 (driver's side) (genuine part).

I last replaced it 7/2019 and IDPusa sent me PN 8501996 which is no longer in their system.

The leaky part is the AIR VENT VALVE PN 9151208 (thanks, IDPusa phone guy). But they don't carry it !

What diameter hose do I need for this portion of the system? I might have to cut some hose so I want some on hand. And some connectors. Volvo only sells complete harnesses.