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Fitting an electric windscreen washer pump.

What you need
1. The pump. 12 volt windscreen washer pumps can be bought from your local motor factors or places like Just Kampers.
2. Around 1 metre of 4.6mm hose (check your pump nozzle size, though 4.6mm tends to be the standard) You may not need any if you existing hose is in good nick.
3. 12 volt Switch - one that only operates if you hold it on. Could be a push in switch or a toggle switch. It's up to you.
4. Bit of wire, an inline fuse (5 amp should do it) and connectors for the switch and pump 12 volt connections.
5. One way valve. This isn't a necessity. It really depends on where you mount the pump.

How to do it
1. If you look up near the base of the steering wheel where it joins the dash you'll see 2 black rubber hoses. One goes to the jets and the other to the bottle. Cut these here. The jet hose will connect to the outlet on the pump and the bottle hose to the inlet on the pump.
2. Remove the kick plate behind the pedals to gain access to the bottle.
3. Find a place to mount your pump. Remember though that the higher you mount the pump the harder it has to work to suck the water through an empty pipe. You could end up in the situation where you need to put in a one way valve to prevent the water from flowing back into the bottle because it hasn't got enough oomph to suck it up far enough.
4. Drill a couple of small holes using to pump mounting holes as a guide and fix the pump in place with a couple of small self tappers.
5. Make up your positive and negative power leads. One to go from the negative terminal on the pump to earth (you'll find an earth point nearby). One from the positive terminal on the pump to the switch. One from the switch to the inline fuse and from the fuse to a positive power source. It might be a bit difficult finding a power source especially if you don't have a Multi-meter. If you've got a radio in your van then you'll have a power source you can tap off there. There are a number of different ways you could attach your new lead to the power source. One of the easiest is a snap on connector which wraps around the live wire and punctures the insulation providing the power to your new spur.
6. Mount the switch somewhere convenient. You'll probably need a big drill so the switch mounts neatly.
7. Time to hook it all up. Connect the negative wire to earth and the pump (you won't know which terminal on the pump to connect it to. Just choose one for now. It won't break the pump just make it run in the opposite direction).
8. Connect the Pumps live terminal to one of the switch terminals.
9. Connect the other switch terminal to the live power feed (with the fuse in between).
10. Connect the pipe from the jets to the outlet of the pump.
11. Connect the pipe from the bottle to the inlet of the pump.
12. Press the button or flick the switch and you should now have a clean windscreen.


- It seems to be pumping the wrong way. Swap the wires over on the pump and try again.

- It seems to be sucking but the water isn't making it up to the pump. You'll need to put a one way valve into the pipe between the bottle and the pump. If your pipe is clear then make a note where the water is making it to and put the valve in just under that mark. Make sure you put the valve in the right way. Try blowing through the valve first to establish the direction it works in. When you put it inline you want to prevent the water from flowing back into the bottle.

- I've fitted the valve but it still isn't making it up to the valve. You'll need to prime the hose then. If the old pump valve is in place then attach a pump and pump the water up to the valve height (make sure the caps are all on tight on the bottle). If the valve is knackered then disconnect the pipe from the pump and suck the water up with your mouth until it is above the valve. Be careful though Screen wash doesn't taste nice!