Had the same problem, pulled them apart and no parts were frozen.  Tightened them up, still flopped.  Bought aftermarket mirrors...they still flopped.  The rubber washer trick finally fixed it.

Dan
Los Angeles, CA
"Winky" the '85 Westy Weekender

On Sep 5, 2011, at 6:27 PM, Don Hanson wrote:

>  My 84s "Flag" stock manual mirror on the driver's side sucks.  I had it
> sort of fixed once, by drilling a small hole through the square post inside
> that is supposed to be the friction axis for the socket.  Mine had pulled
> down from too much tension on the spring....That sort of worked, for a
> little time...but eventually the pin I put through there bent....letting the
> spring post again slip down, losing tension on the spring...allowing that
> irritating mirror to blow back against the window with wind gusts...(and
> there are plenty of wind gusts in the Columbia River Gorge)   So I tried
> peening the socket surface to give it more friction, and epoxied that post
> in after replacing the pin....."Flop!"....it hit the window again tonight.
> 
>  For a while, I had the mirror 'permanently  adjusted' using a hose clamp
> around the base of the mirror stalk and down against the mounting flange
> that screws onto the door....but that was a bit 'Rube Goldberg' appearing,
> even for me who doesn't really need a fancy shiny van...I just don't want
> one that looks too crappy....
> 
>  I don't want to spend $100+ on fancy truck-style mirrors....I actually
> like the Flag Mirrors the vans come with...but they seem to be
> underdesigned.  Surely someone has figured out a way to make them
> stiffer.....Maybe rub them with Viagra or something?
> 
>  Anybody have a trick that works?
> 
>  Don Hanson