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Posted by: 914 RZ-1 Apr 29 2017, 04:45 PM

I'm adding washer fluid pump to my '72. I got a pump and switch. I want to make sure I'm wiring it correctly:

1. Negative on pump goes to ground somewhere on bare metal on car.
2. Positive on pump goes to "LOAD" tab on switch.
3. "EARTH" on switch goes to ground somewhere on bare metal on car.
4. "LOAD" on switch goes to + on pump.
5. "SUPPLY" on switch goes to fuse (#8 or #10, I think), which supplies the power.

Is this correct?

I got the switch at Radio Shack. It's a "push-to-work" and a light on the switch goes on. It needs to be pushed again to shut it off.

I got the pump at Pelican.

Thanks!

Posted by: Valy Apr 29 2017, 05:18 PM

It's right but why don't you use a Porsche wiper switch with electric pump activation?
It's been discussed here a lot. Just search my posts on this topic.

Posted by: 914 RZ-1 Apr 29 2017, 06:15 PM

[quote name='Valy' date='Apr 29 2017, 04:18 PM' post='2480953']
It's right but why don't you use a Porsche wiper switch with electric pump activation?
It's been discussed here a lot. Just search my posts on this topic.

I saw all those. This is easier.

Posted by: BillC Apr 29 2017, 06:33 PM

If you're going to use a separate switch for the pump, look for a momentary-on switch. That way, it only pumps while you hold the button/toggle and stops when you let go.

Posted by: rdauenhauer Apr 29 2017, 07:45 PM

or this


Attached image(s)

Posted by: SirAndy Apr 29 2017, 07:55 PM

http://www.914world.com/specs/tech_el_washer.php

Posted by: Spoke Apr 29 2017, 10:20 PM

On your schematic, swap ground and +12V. +12V should be wired to the pump through a fuse. The negative side of the pump should go through the switch to ground. This way if any of the switch wires accidentally are shorted to ground, you won't blow a fuse.

Also as SirAndy mentioned, the switch should be momentary ON switch, not latching as described.

Posted by: jcd914 Apr 30 2017, 01:35 AM

I am going to disagree with Spoke on switching your wires around.
It is always best practice to make your "normally hot" leg of a circuit as short as possible. That way under normal conditions there is a shorter stretch of wire that can be shorted. In this case that is the wire from the fused power supply to the switch. The fuses are under that dash the switch connections will be under that dash, not much wire there. the pump on the other hand probably will be mounted near washer bottle, significantly farther from the fuse panel.

But he is correct you should be using a momentary contact switch.

Jim