Date: Sun, 18 May 2003 01:13:47 GMT From: ma_twain <ma_twainnopsamo.com> Subject: Re: Washer Check Valves - give me some theory
The story I heard was the spring load valve was designed to open up at a minimal pressure. This was designed to ensure a predictable spray pattern from the start. 'nuther Bob wrote: > I need some help understanding check valves. > > I thought that a check valve would be used like a diode, > i.e. fluid flows one way, but cannot flow back. Or, in the > case of a wiper wash system, the fluid would be pumped from > the bottle, through a one-way check valve, to the washers. > The valve would prevent the line from draining, so the next > time the pump ran the line would be pre loaded - getting the > fluid to the washers faster. Obviously with headlight wipers > this would ba an issue. > > However, that does not seem to be the way the Saab wiper check > valves work. You can't blow through them in one direction. What > gives ? How do these things work ? > > Bob >