'72 windshield wiper/washer problem

[Kurt G.]

I just replaced my windshield washer pump assembly with a new one. Got everything lined up with the wiper motor, but have a minor problem. The washer pump is pumping, or at least trying to all the time, whether I push the washer switch or not. If the wipers are running, the pump is trying to squirt. So, what did I do wrong?

[Jack H.]

Re: '72 windshield wiper/washer problem

From the 1971 Fisher Body Service Manual:

Symptom: Washer pumps continuously when wiper is turned on.

(1) Disconnect wiring from washer pump. If pump shuts off, trouble is in wiring or switch.

(2) If pump fails to shut off, remove pump for further checking.

One issue specific to Corvette is the wiper/washer switch is mounted to the top of the center cluster bezel. That portion of the bezel is prone to cracking when mis-handled by mechanics. The switch relies on its ground reference there which can be affected by a cracked center cluster bezel.

Also, the wiper motor mounts to non-conductive fiberglass of the firewall and it relies on a discrete ground via the engine harness.

Last, what's meant by Fisher's #2 advice is to check the pump for proper orientation of the solenoid latch AND physical integrity of the ratchet wheel/prawl. The pump is designed to 'auto park' after one complete revolution of the ratchet wheel.

If this doesn't make sense to you, the service manual has pictures and descriptive text. But, you should be able to remove the washer cover and physically watch the pump actuate and see why it's not parking...

[Edward J.]

Re: '72 windshield wiper/washer problem

Kurt, Did You Line Up He Pump Cam, If Not The Pump Will Run All The Time, The Cam And Metal Housing On Pump Has A 1/8 Hole For A Drill Bit , If Not Youll Need To Remove The Pump To Re-set,(rotate Pump Cam To Aligne). The Wipers Will Also Need To Be In The Park Position.