I haven't had the 83 240 on the road for over a year, but I decided to licence and insure it next week. It has to pass an inspection for that, so I checked out all systems...dang! wipers do nothing on any setting of the switch. I had noted when last used that they were sluggish.

Tracing the circuits showed 12V everywhere it should be, including the connector at the motor. Pulled the motor and tried running it disconnected from the linkage, with an alligator clip on the diecast gearcase wired to a ground. Bingo.

One of the motor mounting legs has a little tang that grounds the gearcase to the firewall under one mounting bolt. This gives the ground current a path, since all legs are rubber mounted. It was corroded and so was the body metal right underneath. Sandpapering to clean metal on the tang and sheet metal resulted in working wipers.

Side note: with the wiper motor assembly removed, its hole in the firewall revealed a slug of damp evergreen needles in the cavity there, from the years the car parked under a giant Spruce at my former house. I'm guessing they get there via the cowl vent system or its drains? A coat hanger and a shop vac got a lot of the mess out, about half a cupful of needles. Trapped, damp vegetation has to be a great way for rust to flourish.

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Bob: son's XC70, dtr's '94-940, my 81GL, 83-DL, 89-745(V8) and 98-S90. Also 77-MGB and some old motorcycles.