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Discussion Starter · #1 ·
I have looked and seen there are many threads re wiring for a washer pump, my question is slightly different.
SO,,I have just purchased a 66 coupe with no washer pump or hoses etc. I brought a kit to install the washer jets and all the water hoses etc. I had a small modern washer pump on the shelf so am intending using that. There is no wiring adjacent to the pump, but up near the firewall close to the brake master cylinder I found this (see photo). I have tested the two wires from the duo plug, and one of them does become live when you pull the wiper switch. The other half of the plug does not appear to be an earth. There is also a third chopped off wire close to the plug (photo). This third wire may be nothing to do with the washers of course. Can anybody shed any light please ?
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Discussion Starter · #4 ·
That would be great, thank you. So you are both saying that the duo plug are live and earth for the pump. Trouble is the live seems intermittent, and the earth does not seem to earth. I am wondering if the switch is dirty and not working properly ?
 

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Discussion Starter · #18 ·
^ to test this theory, you could use either a Volt meter earthed/grounded at the pump must location, or a test light hooked to the pump location. Then use the hot probe on each terminal of the duo connecter with the switch on speed one, then on speed two to see if you get voltage or a light.
That's a good idea, I will try that. I have a 12v test probe with a bulb. SO if they both happen to be live...which one should I use ? or does it not matter. BUT if they are both lives (HOT when switched) wouldn't they both be insulated at plug, instead of just the one ?
 

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Discussion Starter · #19 ·
Looking at the 1966 wiring diagrams, one wire should be live coming from the wiper switch when the washer pump is being activated. The other is earth (ground) coming from the wiper motor and to the washer pump. The wire coming from the switch to the two prong connector is Black/White. That will be your live wire.

View attachment 841885
That's brilliant, thank you so much. I suspected that if one pin of the plug was live then the other would be a ground. I will have another look tomorrow.
 

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Discussion Starter · #23 ·
66 two speed wipers ground at the wiper motor through a set of contacts. It uses a different style of pump and squirts by the on/off cycle of the contacts. To use your "modern" pump, use the wiring harness "hot" wire then ground the pump to the pump mounting bolt. The wiring harness ground back to the wiper motor will be unused.
So, use just the hot wire at the duo plug only, then just earth the pump to the mounting bolt ?
 

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Discussion Starter · #25 ·
That makes sense, I didn't take that into consideration when I came to my conclusion. After looking at the posted wiring schematic, it appears you are correct.
It just makes sense to me that they would be a live and earth. I will try and understand that wiring diagram LeeFred sent, but I usually find diagrams confusing.
 

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Discussion Starter · #26 ·
Thank you again for taking the time to download the wiring diagram. So I think it should work as I tried on my first test. I am getting voltage with a test light at the duo plug. I am wondering if it is just enough voltage to light the small bulb in tester. I will try some contact cleaner on the back of the wiper switch next.
 

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Discussion Starter · #29 ·
Just an update to everyone who has tried to help with the washer pump problem. ..I haven't got any further with it yet, but hope to get back to it in the next few days. Just something that occurred to me though. I take it that the washer pump is supposed to work without the wipers being switched on ?

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Discussion Starter · #33 ·
Sorry, yes...a bit of confusion there. BUT if I do as you suggest above it will then work without wipers being switched on...yes ? ( I am just trying to get all my facts straight before I tackle the job again.
 
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