67 Cutlass. Had to replace the washer pump, all I can find are these cheap replacements, gone thru 4 now, 2 did not work (they were defective) and the other 2, 1 on which is on the car now, pump water whenever the wipers are on. And that is with or without the wires attached to the pump. Any ideas? Thanks.

 

Found an old post that said problem would be in the wiper motor. Changed out the motor for a new one and have the same problem.

 

Could it be the control switch on the dash?

 

Unplug the connector going to the washer, dark blue and yellow wires, and see if it turns off. If it still operates the washer then the problem is in the pump mechanism. If not, then you are getting a constant ground signal from the switch or wiring.

 

I don't know if the 67 system is the same as the 70-71, but I had a similar issue years ago and it was due to the plastic pawl not engaging the wheel properly. One of the pawl arms was bent slightly and didn't engage the notches on the wheel, so the wheel stayed in the same place instead of making a revolution and turning the pump off.

 

That one is different but likely works on the same principle. Disconnecting the wires to the pump make no difference. All are new parts now, and same results.

 

There is something wrong with your pump actuator if it sprays while disconnected.

 

I would think so. When ignition is on but wipers off, all terminals light up a test light grounded to the wiper motor. The three on the wiper motor and the two on the pump. When wipers are on, only the top wire (on the 2 wire harness) to the wiper motor lights up, as well as both leads to the pump. Hmmm.
BTW here are a few pics of the finished product.

 

Sweet... The motor and the pump have power at all times with the key on, the wiper switch provides a ground signal to each when selected.