Originally Posted by Smoothie
@Thrall. How do you flip the pumps? I have heard people running the wires opposite. Black Ground to Red and Red to Black Ground. That way you can flip the pump and it will fill and empty properly according to your switches.
WHen you flip the pumps, take the pump head off and rotate it 180 deg. I did not do this, but learned of it later (on TMC here). That will get the correct rotation wrt the switches without cutting wires. Right now mine is fill=empty on the switches because the switches looked like a pain to flip, wires all tightly bundled. I'll spin the pump heads next time I need to tear into the impellers, which by the way if flipped, the rear impellers are harder to access.
The rear pumps can be flipped without doing anything to the hoses, but they need to be mounted lower with only 2 of the screws. WOrks fine since the hoses pretty much hold the pumps in place anyway.