[bigreen505]

I'm starting to think that there is a design problem with the rear wiper. I've tried three now (Subaru, Bosch, Trico beam) and they all have the same problem. The ends contact the window, but the center where the wiper mounts to the arm does not.

 

[SilverOnyx]

Could it be spring tension on the arm itself that's the problem?

 

[bigreen505]

Could it be spring tension on the arm itself that's the problem?

Maybe? Not sure how to check or adjust that.

 

[SilverOnyx]

Maybe? Not sure how to check or adjust that.

Me neither but I suppose I could put a kitchen scale under the arm to gauge the pressure? After trying three different blades and all of them have the same problem, the arm and glass are the only constants, and we can't change the glass.

 

[ByebyeVolvo]

I fully agree that insufficient pressure is the problem. And I can't see how one might alter/adjust it. Both the plastic and metal frame Bosch rears are unacceptable and I replaced the original Subaru because it wasn't doing the job either. A rear window center smear is by far my biggest pet peeve with an otherwise excellent winter driver (audio quality issues notwithstanding!)

 

[SilverOnyx]

I wonder if cold weather exacerbates the problem - I'm in a tropical climate and mine doesn't have the center smear/gap problem.

 

[ByebyeVolvo]

Well, from a semi educated prospective - pressure on the glass should be a function of spring tension, yes? The spring is metal. Metal expands when hot, shrinks when cold, if my liberal arts education serves me well (???) If the spring has shrunk/contracted with cold, that should create more pressure....

 

[SilverOnyx]

Well, from a semi educated prospective - pressure on the glass should be a function of spring tension, yes? The spring is metal. Metal expands when hot, shrinks when cold, if my liberal arts education serves me well (???) If the spring has shrunk/contracted with cold, that should create more pressure....

I was thinking of the spring in the blade itself not the arm!

 

[ByebyeVolvo]

You might have a point, but I’m convinced the arm is at fault. There is virtually no “snap” when I return it to the operating position. I should try holding finger pressure on the arm while it is in continuous mode.

 

[SilverOnyx]

You might have a point, but I’m convinced the arm is at fault. There is virtually no “snap” when I return it to the operating position. I should try holding finger pressure on the arm while it is in continuous mode.

It might be possible to piggyback a second spring or install a slightly stronger spring.

 

[ByebyeVolvo]

Actually, as I think about it, I believe the arm spring would be in a relaxed position when the arm is against the glass - and stretched only when the arm is raised.....so......just dunno. This is something I would love to find a solution for but a couple of quick looks have given me no ideas yet.

 

[SilverOnyx]

 

[ByebyeVolvo]

I haven’t worked up the gumption to try to pull the arm off yet...just fussed with it enough to understand that it won’t necessarily be easy. Might try after I get home next week from tomorrow’s long road trip.

 

[bigreen505]

A rear window center smear is by far my biggest pet peeve with an otherwise excellent winter driver (audio quality issues notwithstanding!)

Yep exactly that.