Ive been getting to the bottom of my fuel delivery problems. Slowly but steadily when time allows. There was considerable air getting in the system likely from the fuel filter bolt o rings, since replacing them and the hand primer pump, its managed to start again and run with less problems.

I purchased a Mityvac, well worth it as it gave me an Idea of where the air was getting in and could isolate the problem quicker. There seems to be some air still getting in from somewhere around the fuel filter. Ive noticed with the handy gauge on the Mityvac it shows vacuum/pressure/resistance of about 2 or 3 in.Hg (or 5 kpa). very little anyways. but when I hook up the mity vac to the line that exits the primer pump assembly, before entering the IP (I think?) the resistance increases considerably.

Fuel wont start flowing when I pump it until the needle reaches 5 or 6 in.Hg (or about 17 or 18 kpa) is this normal? and if not could there be an easily remedied problem in the primer pump assembly like a stuck valve or something. I replaced the hand primer pump with a new one as the old one was definitely leaking fuel, however in a series of primer pump changes by the mechanics they put the old one on and left out the copper washer, and I tossed the old one. a new one is on order but in the meantime the car has run without it. Is the pump assembly easy enough to remove?

I have same as the one on the right. It looks as if I may simply have to loosen the large bolt in front of it? On pictures of new ones on parts ordering websites it shows the opposite side with 3 holes and a gasket. Are these holes for a bolt or an allen wrench? I cant see without taking all the hoses and parts off. Any suggestions as to how to go about doing this and/or if the resistance the pump seems to be causing is normal?