First off, fortunately it doesn't rain too much here in So Cal. With that being said, the wipers on my newly acquired '66 F-85 wagon are acting weird and I need help. When turned on, they might make a complete wipe, sometimes stopping in the middle of the wipe. Jiggling the switch sometimes works, but I haven't had the car long enough to get to know it yet. Any suggestions on what to look at as electrical isn't my strong suit.

 

If the dash switch isn't grounded well to its strap, and strap to dash, and body to engine [rear end of RH head] then I think the signal to run is lost.

The Chassis Service Manual has an extensive section on troubleshooting the wipers.

You could tighten the switch in the dash, and if that does not do the trick, pull the switch and test it with an ohm meter for proper continuity. If you don't know how, now is a good time to learn.

 

You may need to open the gear box on it, as the old grease gets very hard and will jam it up. I had the same problem on my 65 Vette. Cleaned it greased it, works like new now. I also thought it was an electrical problem, but it wasnt.