Installation and first system testing

[GCCR]

I have a system 2c with a Race spec pump - bought second hand. I've wired everything up and now want to check that the pump pumps water under pressure properly. To begin I just connected the 1 and 3 inputs to the pump to 12V + and -. The pump runs but does not suck in the water much less squirt it out under pressure.
I've tried with a non return valve on the inlet side and bled all the way to the pump inlet ..... and with the water container about 1 ft above the pump but it doesn't seem to work - despite the noise from the pump.
Can anyone suggest what else I should be doing to check the pump functions properly ? Before I send back to ERL for checking that is. :cry: