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Discussion Starter · #1 ·
On my '73, I cannot get the washer to pump water. I have replaced the hoses and verified the lines are clear but I cannot tell which wires control the wipers vs the washer pump so cannot test just that. With wiper motor running, I cannot hear whether the washer pump is making any noise. Any suggestions?
 

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On my '73, I cannot get the washer to pump water. I have replaced the hoses and verified the lines are clear but I cannot tell which wires control the wipers vs the washer pump so cannot test just that. With wiper motor running, I cannot hear whether the washer pump is making any noise. Any suggestions?

The two wires that plug into the upper front are the wires that control the pump. One wire is constantly hot (with the key on) and the other wire gets momentarily grounded when you press the washer button. Once the button is pressed the washer will deliver 10 pulses. The older pumps often quit pumping because the toothed nylon sprag inside stripped and the only way to repair them is to replace the whole washer unit (about $75). But then I found the new pump assemblies have poorly made cylinder heads for the pump portion so I had to use my old cylinder head over again (the part where the 3 hoses connect).
 

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Thanks. Is there a way to test JUST the pump without activating the wipers?

Nope, because the wiper motor is what drives the pump. If you want to know how it works I suggest taking it off (just 3 screws) and look inside.

If I had to do it over again I would use an electric motor powered pump like an '82 has and then adapt the pump to your reservoir. Then when you push your button the pump would run as long as you keep the button depressed. And the '82 pumps only cost about $25...................
 

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Discussion Starter · #5 ·
Nope, because the wiper motor is what drives the pump. If you want to know how it works I suggest taking it off (just 3 screws) and look inside.

If I had to do it over again I would use an electric motor powered pump like an '82 has and then adapt the pump to your reservoir. Then when you push your button the pump would run as long as you keep the button depressed. And the '82 pumps only cost about $25...................
So I probably have a bad pump, right?
 

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Discussion Starter · #6 ·
So I probably have a bad pump, right?
I should add that I have verified power to the wires in the front and side you mentioned and pulled off the 4 screws on the side where the water enters and exits the hoses and that all looks good. No crcked gaskets or split diaprams.
 

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So I probably have a bad pump, right?

When you push the button in the pump should make 10 audible "clicks"; each of them being one "pulse" of the pump.

Inside the housing is a solenoid and when that solenoid gets energized it shifts a link that gets the pump in motion. The pump itself seldom goes bad but the 10-tooth ratchet does as one or more of the nylon teeth get stripped.

Did you take the pump cover off and look at the inside of it? You can run the pump with the cover removed as it's only a dust cover that serves no other purpose.
 

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I should add that I have verified power to the wires in the front and side you mentioned and pulled off the 4 screws on the side where the water enters and exits the hoses and that all looks good. No crcked gaskets or split diaprams.

When your wipers are turned on there should be power to one of those front two wires. The other wire goes to the speed selector switch behind the button and gets grounded when the button is depressed. Once grounded the pump will cycle 10 times; each time delivering a shot of water to your wiper arm/blades. And it should make a click click click click click click click click click click sound. After those 10 clicks the button needs to pressed again to continue the pumping.

So what is it's status right now? Is it off? Have you checked to see if one of the two front wires is hot when the wipers are going?

E-mail me.......................it's easier for me to explain things outside of the forum
 

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Discussion Starter · #9 ·
When your wipers are turned on there should be power to one of those front two wires. The other wire goes to the speed selector switch behind the button and gets grounded when the button is depressed. Once grounded the pump will cycle 10 times; each time delivering a shot of water to your wiper arm/blades. And it should make a click click click click click click click click click click sound. After those 10 clicks the button needs to pressed again to continue the pumping.

So what is it's status right now? Is it off? Have you checked to see if one of the two front wires is hot when the wipers are going?

E-mail me.......................it's easier for me to explain things outside of the forum

I am going to work on it this afternoon. Thanks for the tips. I will email you direct, I wanted some of this on the forum for others to learn from as needed.
 
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