Is fuel filter unidirectional? Options

[andreic]

I just replaced the fuel pump and all the fuel hoses on my 1972 Porsche 914 1.7L. Now I don't get any fuel pressure when running the pump.

The pump (3 port) was refurbished by one of the members here, and looks very good. But I did not test it outside of the car. When I apply power to it it certainly runs.

All the plumbing was redone to respect the original plumbing. So far I have checked that there are no kinks in the lines, and I have attached a fuel line to the fuel pressure port (on the driver's side injection rail) and put the other end of it in a portable gas can. Nothing comes out of it when running the pump.

The one thing that I wonder is if the fuel filter could be the issue. I bought a cheap one from amazon, which looked exactly like the original one (like a cube) but turned out to have one port 1/2", the other 5/16". As it is plumbed now, the fuel line from the tank goes to the 1/2" port, and the 5/16" port is hooked up to the intake of the pump (port farthest away from the check valve on the pump).

Could it be that the fuel filter is completely choking the flow, if it was installed backwards?

Another thought I had was that maybe when the pump was rebuilt, maybe the wires at the electrical connector may have been switched, and the pump now runs in reverse. Is there any way to check that? (When I run the pump, I can sometimes hear gurgling in the tank, as if air was being pumped in, but as I said there is no fuel pressure.)

Thanks for any suggestions,
Andrei.