1974 windshield washers

[Bill E.]

Hello all,

I'm trying to get the windshield washers to work on my '74.

I have removed and inspected the valves and o-rings in the white plactic assembly atttached to the wiper motor. I primed the pump and blew on the hose until water came out of the jets on the wiper arms. I re-primed the pump, started the wipers and activated the pump, still does not work. When I push the washer switch I can hear the pump kick in but about once each full revolution of the wiper motor there is a snapping noise. This only happens when the pump is activated. I'm wondering if the connecting rod on the pump piston is broken.

How do I get to the mechanical part of the pump to check it out? I've looked in my catalogs and it seems like the '74 pump is unique and I can't find any repair parts other than o-rings. Will the wiper motor have to be rebuilt just to fix the pump? Thanks in advance for any help. Bill

[Michael W.]

Re: 1974 windshield washers

As far as I know your pump is mechanically identical to all earlier year three port pumps and the parts are interchangeable.

The loud 'clunking' is usually due to the pump ass'y being assembled to the wiper motor housing without the pump cam first being indexed properly. If you remove the pump ass'y, you will see a hole in the drive cam. If you then rotate it manually, this hole will align with a similar one in the housing. Use a small drill to hold the two in position and reinstall the housing on the motor.

This might the source of your no-pump problem.

[Bill E.]

Re: 1974 windshield washers

Thanks Mike, can I take the pump assembly off the motor without removing the motor? There is a black plastic cover over the motor, I can't see how it is attached. Is there a screw holding it on the bottom? I didn't see one and didn't what to force the cover off and break it. Bill

[Jack H.]

Re: 1974 windshield washers

You should find the black plastic cover simply 'snaps' into place on the WSW pump assy. Once it's removed, you'll find the mounting screws that hold the pump onto the wiper motor. BTW, this disassembly IS covered in the Chevy Chassis Service Manual, which if you don't have a copy in your support library, I'd suggest you get one...see the STORE button on this web site.

[Bill E.]

Re: 1974 windshield washers

Hi Jack, good to hear form you. Thanks for the info. I have the Chevrolet Service manual, but not he Chassis Service Manual. Unfortunately when I checked the store section I found it is out of print. I'll scout around and pick one up. Bill

[Raymond W.]

Re: 1974 windshield washers

Bill,

Maybe you have a different or more serious problem, but I had similar symptoms with my washer pump as well (remember the NE Chapter Meet). I too inspected the O ring and it "appeared" to be just fine. Before you go through a disassembly of your pump, go to Auto Zone and pick up a washer pump replacement kit. I replaced only the ballentine styled O-ring, reusing the weathered/yellowed plastic assembly. My windshield washer works just fine now. Good luck.

Ray

[Bill E.]

Re: 1974 windshield washers

Hi Ray, did your pump make a snapping noise at each complete cycle of the wiper motor?

Bill

[Raymond W.]

Re: 1974 windshield washers

Can't recall if it was a snapping noise, I remember it to be more like a clicking noise. Unless you've already gone the next step of disassembly, try replacing the O-ring first. See what results you get.