Hi Volks,

I have used a vinegar/water solution to clean my windsheild washer
ports. The deposits which are constricting the openings are calcium
carbonates which precipitate over time when minute amounts of washer
fluid evaporates at the opening.  Over time these deposits clog the
opening.

Vinegar is a weak acid and will dissolve the calcium carbonate.  I would
start with slightly diluted vinegar.  I've used this solution plus a
small wire or pin to help scrap the precipitate from around the
opening.  It will also help to remove deposits in the lines.  Its like
cleaning your coffee maker.

Hope this helps,
Ken Wyatt
82 westy