Other than the obvious of turning it on, how can I tell if my motor is bad. I filled up the fluid and push the button, nothing happens- does it need to be primed? How do I test circuit?

The Windshield Wiper Washer does not have a Motor but rather a plunger that engages a Star Wheel which is constantly driven buy the Wiper Motor when the Washer relay is activated and runs through a Cycle. The Plunger works on a dual Pump Diaphragm. one for each side. Yes they usually require priming. If it doesn't work you may require a Diaphragm Kit or the Plunger Relay Switch is not engaging the Star Wheel properly.

It is almost impossible to trouble shoot problems with these units without having it right in front of you as they are a rather an archaic complication of inter-connected mechanisms but are not that difficult to figure out if you take it apart and see for yourself.

Other then the Pump Diaphragm rotting and dirty relay contacts the biggest problem associated with these Wiper Systems is that Lower Motor Bearing seizes and the motor stalls simulating no power. In which case you have to lift the stator out of the lower bearing as not to disturb the brushes in order to lubricate it. A good ground is essential for the motor and internal relays to work properly.

To me the Old Pump System is a novelty when working. If you want it by all means spend some time on it but to tell you the truth an Electric Pump Washer is far more convenient and reliable and easy to wire into to the Existing Dash Switch.

NOTE: Other posts re: Wiper Systems. Most of the material your looking for is covered in them.

The BEST way is to do a Bench Test; that is take the Wiper Motor off the car, remove the Covers and wire the terminals to a 12 Volt Battery and observe how the mechanism works.

Before you go nuts tearing things apart, make sure the screen on the end of the pickup hose in the tank isn't clogged. I replaced a pump once and found this problem after.

To bench test one I used my battery trickle charger. It makes 12 volts and enough amps to get the pump turning. HTH;)

Thanks 12run and micro-good tips- Hey Micro- how do I hook up the trickle charger