Question

No water at sink or toilet, I have Shurflo Diaphragm Pump, 4.5A max, 16psi pressure, 7L/M. When the pump is switched on, the motor runs and runs but does not pump any water to the sink!

Answer

This is probably a diaphragm problem in the pump, considering yours is a 16 PSI I am presuming it is quite old, the date will be on the data label. You can just replace the diaphragm but if the pump is old it would be more cost effective to replace the pump with the 20 PSI model. I have put the links below for the diaphragm and the complete pump \r\n\r\nSHURFLO PUMP VALVE KIT - ALL 2095 SERIES\r\n\r\nSHURFLO DIAPHRAGM DRIVE KIT 7LT PUMPS \r\n\r\nSHURFLO TRAIL KING 7 PUMP 20PSI 12V