I removed both wiper arms on my '80 242 so I could remove the rubber boot and finally reapply the pin-stripes (Thanks, Roger from Florida ! Great stripes).

The driver side arm came off and goes back on fine. On the passenger side, however, it came off the wiper transmission differently than on the other side, and now won't go back on.

You have, from top to bottom, the arm mounting point, threaded -- a little "ferrule" about 1/2 inch long, and the threaded pivot post from the transmission that protrudes through the cowl. The arm basically sits down on this ferrule, which then sits down on the pivot post. This ferrule appears to be some sort of size adapter. Volvo book shows it as part of the transmission assembly - not available separately.

On the DS wiper, the ferrule remained intact and remained on the post. Arm slips back on firmly. On the PS, however, the ferrule broke apart. Without the ferrule, there is no way to match the threaded wiper arm mounting point to the threaded pivot post (different sizes). They different sizes -- the pivot post is smaller than the threads inside the wiper arm mounting point. And, to bgoot, it's apparently receded a little bit (dropped back down into the cowl). Maybe that ferrule held it up ???

Any ideas, other than replacing at least that part of the transmission from inside the dash (not something I relish) ? I already ruled out JB Weld, but I suppose if all else fails, at least I'd be able to change out arm springs and wiper blade arms......