The San Diego region, and SouCal in general, can always use some rain so yesterday morning I went about thoroughly cleaning my windshield and fixing my windshield washer system on my Nissan pick-up. The washer was down to one weak stream on the driver’s side and I took that as a sign that I should maybe address fixing the on-board squirt gun devices.
It went in a straightforward manner: I replaced the old hoses and removed the squirt guns from the hood. As I suspected they were clogged with come sort of blue calcification crap and used a 0.020" wire to clean out the openings and the manifolds. Replacement went fine and they now work like little charms.
Funny thing was that there were three back-flow check devices in the washer lines. they needed cleaning too but were easily cleaned. One was just downstream from the washer fluid reservoir and the other two maybe three inches upstream from the squirters themselves (i.e., just under the hood). They was nothing in my Haynes manual about them but I found a website that mentioned such things as components in a washer system.
My question is: What the heck are they there for?!
I would have thought it would be a good thing for the washer fluid to siphon back down to the reservoir so there’d be no water in the lines to freeze up when you would need the washers the most. What gives?