There is an article at vanagonauts.com (i think) that details the nitty gritty of cleaning the splines of the sacrificial metal from the wiper arms.  Mine were constantly flopping after tightening until I did this.  Now using Bentley torque values they behave like they should.

 

Ryan
 
> Date: Tue, 3 Mar 2009 11:15:07 -0800
> From: gsm@GREGORYSMORRISON.COM
> Subject: Loose wiper arm
> To: vanagon@GERRY.VANAGON.COM
> 
> I know there was a very recent thread on how to fix a loose wiper arm, but I
> can't find it in the archives. Our passenger side wiper arm is really
> starting to flop around and the splines are very worn. Can someone please
> forward "the fix" to me? I would prefer to not have to tear out the entire
> dash assembly nor have to hunt down a part that's no longer available.
> (Wishful thinking?)
> 
> Thanks,
> Greg
> 86 Westy Syncro

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