C2 Windshield washer pump

[Garry E.]

I am about to loose what little religion I have left in trying to get the wihdshild washer to work on my '64 roadster..... I ordered the white external cap and stuff from Long Island CV..... When I took off the original (was formeraly a clear or dull yellow color...) and inspected the pump diaphram, it appeared to be in good shape - no holes or rips. Put the new pieces on and still doesn't work.... Tried priming the pump by running water from the resevoir hose back into the pump - still nothing..... The wipers work fine

Any thoughts?

[don 42616]

Re: C2 Windshield washer pump

Garry , I had to have internal pump replaced. It can be done w/o removing motor. Don

[Alan Drake]

Re: C2 Windshield washer pump

Gary,
Is the main piston moving up/dwn? Must have cover off to verify, however I had mine on bench so not sure if you can check in car with front cover off.

I used the repro rubber parts to replace the old one's in my plastic cover. Note the replacement is in two sections and not correct looking from the outside. Also try filling the line with water first and let gravity feed (testing).

Although my main piston rubber looked OK, I replaced and it then started to work. This part is another order and normally note part of kit.

[Jack H.]

Re: C2 Windshield washer pump

The factory original WSW pump in '63-64 used a 1-piece nozzle/valve assy made by Rochester. It was a translucent colored plastic that's notorious for drying out, turning yellow and cracking. The umbrella valves in the nozzle assy are metal housings with black rubber in the center. They were press-fit into the plastic valve assy, then hot melted in place. The common reasons for these pumps to stop working are:

(1) Umbrella valves (rubber in the center of the metal surrounds) have gotten hard/brittle by being left dry over time. Not much of a solution here...

(2) The umbrella valve assy's have 'lifted' from their press-fit/hot-melt positions in the nozzle assy and you have blow-by leakage. Solution: clean and attempt re-insertion with an appropriate sized socket to spread the insertion force.

(3) The plastic valve assy has dried out, cracked and is leaking. No solution.

(4) The pump's rubber piston has dried out and cracked. Solution = replacement, it turns 90-degrees to release from the actuator.

On #4, the rubber piston is long discontinued but repro's are available from catalog houses like Long Island. My experience with the repro replacement isn't good. They're very thin wall rubber and prone to ripping on installation...

Test the overall pump for seal integrity by FORCING water through the inlet nipple while it's inactive. If the pump's internals are in good condition, you can actually blow water through the inlet umbrella valve, into the pump piston, and out the outlet umbrella valves causing fluid to reach the squirters. If she's leaking, expect no fluid to exit the squirter and observe fluid dribbling from the pump itself. Until you can pass that diagnostic (forcing fluid in/out of the pump), you're spitting into the wind trying to get the pump to work!

As mentioned, replacement valve assy's are of the 2-piece construction (plastic nozzle + plastic valve plate & rubber grommet to seal) characteristic of '65-67 Corvette WSW pumps. Occassionally, a good, used original, 1-piece Rochester nozzle assy comes up on eBay, but they're as rare as hen's teeth and tend to sell for $40-80 if factory concours authenticity is your objective...

Last, once you get your WSW pump working, do NOT let it go dry! That's what kills them (inactivity). Periodically, exercise the washer pump during storage to keep it primed and moist.

[Mark P.]

Re: C2 Windshield washer pump

I had mine apart in my 65 and got it rebuilt and when I got it back together, it woldn't work. I tried and tried and finally just decided that there was no reason for it not to work and that it just needed to be primed. I disconnected the line from the nozzle and pushed the button and sucked for all I was worth (no comments necessary). I was about to give up trying when it finally came through. I rinsed out my mouth and now we're both working fine. It took several tries, so be patient.

Hope that helps solve the problem (I hope it's that simple).

Good luck,
Mark