I really wish I'd read the whole letter before typing that.... heres the link to the fix! http://www.totalbmwmag.com/HandsOn/TechAug01.PDFquote:
The old-style headlamp wipers are notoriously unreliable, but there are a few simple things you can do to sort them out.
Firstly, apply 12V directly to the motor - if nothing happens when you do this, the shaft is seized with rust. The rubber seal over the arms was never very good and on most cars will have probably perished years ago, allowing the water in.
We've managed to free up a couple of motors by dismantly them, knocking the operating shaft out of the mounting tube with a long rod and hammer, then running a drill up the tube to clear the corrosion. Use fine wet-and-dry paper to clean up the shaft and polish it with a metal polish like Brasso, before reassembling it with the tube packed with grease.
If you're lucky, the motor won't have burned out and your headlamp washers should be working again. It all depends on how long its been seized.
We covered this procedure in more detail back in our August 2001 issue. You can download the full feature by visiting our website.