Windshield Washer for S1 1.3S

[4thinline]

A PO replaced the original windshield washer on the dash with a push button (the one to the immediate right of the 3 white switches on the dash). I was going through a box of parts and found the original dash knob/switch. How does this work and is it possible to test it before installing it?

It has no electrical connections, only what I assume are two tube connections on the back (one coming from the bag and the other going to the windshield I assume). How does the switch work? I notice you can pull out the knob and the manual says something about pulling it out to get the washer to spray the windshield. Is this the pump? I have no idea how this works, how to get it to work or how to test it. Can I take it apart? Any help is appreciated. Thanks.

[Taddraughn]

You have to pull it fairly hard, but it is a manual pump! You can probably just stick your fingers over where the tubes would connect and pull it out all the way to see which one sucks. The hose going into the box for the wiper fluid should have a small one way ball check valve too so that the water doesn't just fall back into the reservoir

[Marnix]

Manual pump. You pull out the knob against the strong spring, and then the spring pushes the plunger back in pumping some fluid out. There are TWO small ball valves in the lines (one in each line). The pump itself doesnt contain valves.

[Taddraughn]

Manual pump. You pull out the knob against the strong spring, and then the spring pushes the plunger back in pumping some fluid out. There are TWO small ball valves in the lines (one in each line). The pump itself doesnt contain valves.

I must have missed the ball valve in the tube going to the washer nozzle.. Is it supposed to be located near the pump or closer to the nozzle?

[bmarler]

Manual pump. You pull out the knob against the strong spring, and then the spring pushes the plunger back in pumping some fluid out. There are TWO small ball valves in the lines (one in each line). The pump itself doesnt contain valves.

hmm, didn't know that. i imagine a lot of pumps were discarded due to faulty check valves.
i wonder if there's a source for the valves?

[Marnix]

I must have missed the ball valve in the tube going to the washer nozzle.. Is it supposed to be located near the pump or closer to the nozzle?

Heu... any (piston) pump needs a valve at the input and one at the output. Same as your engine actually, which can be seen as an air pump with internal combustion.

The valves were somehow inserted into the plastic tubes... I do not recall were exactly they are situated, my guess is the output valve would be close to the pump, i.e. behind the dash.

[Marnix]

hmm, didn't know that. i imagine a lot of pumps were discarded due to faulty check valves.
i wonder if there's a source for the valves?

The originals seem to have rusted badly (it is a ball valve, but they didn't even use stainless balls , that's asking for trouble).

I have been buying something similar from Ebay, but it wasn't very good stuff (they are stuck again). The whole sprayer system is one of the items on my list waiting for a complete revision. I haven't seen any supplier offering these (which doesn't mean it is not offered somewhere that I do not know about).

If somebody finds this, give a yell...

[bmarler]

i know these are designed for air systems, but i've used them for water before. there's a selection of tubing sizes available. i might buy a bag of them to try as i have the pump from my appia removed and can test it there.
https://www.automationdirect.com/adc..._valves/cvu532

[4thinline]

Thanks for the assistance. The knob pulls out about an inch (25mm) and I can hear the diaphragm inside. The diaphragm seems to be OK as I can't blow through the back nozzle with knob all the way in but I can if I pull the knob out. Because it closes completely when the knob is in I'm wondering why the need for a check valve on the upstream side. Pretty strong spring on that knob.

[Marnix]

Because it closes completely when the knob is in I'm wondering why the need for a check valve on the upstream side. Pretty strong spring on that knob.

When you pull the knob out, you got to make sure you are sucking water up, and NOT air from the washer nozzle instead! (tank valve open, valve to the nozzle closed). When the spring pulls back in, the water being sucked up previuosly need to go to the nozzle, not the tank (valve to the tank closed, valve to the nozzle open). It is simply a piston pump, but instead of having the valves in the pump itself as usual, the valves are externally in the lines. A piston pump ALWAYS got an input valve and an output valve….