Vacuum Pump Tests

Connect a jumper wire between terminals No. 4 and 8, and between terminals No. 7 and 8. Vacuum pump must run and fully retract activator diaphragm. Remove jumper wire from terminals No. 4 (terminals No. 7 and 8 still connected). Pump stops, but diaphragm remains retracted. Remove jumper wire from terminal No. 7 and diaphragm should extend. If results are not as specified check: vacuum hose/connections, vent valve/adjustment, wiring to vacuum pump, vacuum pump.