Fuel pump funk

[Thaiyoon]

When I started to bring my 521 to life after it had sat in a field for 7 years, I noticed that no fuel was pumping through the fuel pump. I assumed the fuel pump was bad so I bought the only mechanical pump that Napa had listed for a 70' 521.  I had bypassed the main fuel tank (full of gas turned turpentine) and gone straight from a gas can of fresh fuel raised above the fuel pump, through the fuel pump, and into the carb.  The truck would run then and even idle.  Since then, I cleaned the main tank and all lines are clear from the main tank to the fuel pump.  Yesterday, I filled the tank with fresh fuel and connected all the lines up and expected fuel to start being drawn up from the tank.  No fuel appeared to be filling the filter.  I disconnected the inlet fuel line at the pump and was easily able to suck up fuel from the main tank and fill the fuel filter.  I reconnected the fuel line to the pump and still no start.  I took off the outlet hose from the fuel pump and attached a clear line to see if any fuel was exiting the fuel pump.  Nothing.  I thought maybe I had poorly installed the fuel pump (wrong side of the cam) so I took off the valve cover and it appeared to be where it should be.  

 

The first video is cranking the engine, with the fuel pump in position and fuel at the filter but shows no fuel exiting the pump even after pumping  for a while.

https://www.youtube.com/shorts/xOOz80_-oUQ

The second video shows the fuel pump removed, but pumping the same set up by hand.  As you can see, fuel seems to flow liberally.  

https://youtube.com/shorts/cZvx4ebwmxQ?feature=share

My question is, did I get a bad fuel pump?  Is it a good fuel pump but the wrong one?  Is there a fuel pump designed for the motor that gets pumping action with less throw (the amount the cam is moving the pump arm in the video)?  

 

Napa is ready to consider the unit I have as faulty and give me a full refund.  

 

What do you recommend?

 

Thanks for any help you can send my way.

 

 

[datzenmike]

I sem to remember fuel gushing much more than that.

 

Is there a 1/4" plastic spacer between the pump and the head? If yes, take NAPA up on their offer and find another.

[Thaiyoon]

Thanks again, Datsun Mike.  I did have the spacer in place.  I opted for an O'Reilly's fuel pump to replace the Napa unit and the truck is now idling and running merrily.  Best to you all.

[banzai510(hainz)]

fuel pump  look kinda low output but at idle it should have still worked as it hardly uses any gas