Volvo Repair: 1977 volvo wont start, distributer cap, flapper valve

Question
I have a 1977 volvo that won't start. I have replaced the one fuel pump but not the one in the tank. I know it is getting fuel. I replaced the fuel filter and gas flows out of it freely. It is getting spark at the coil and the plugs. Distributer cap is new. It will start with starting fluid but won't stay running. Any ideas?

Answer
Bunny,
      It does sound like fuel related problem.
        MAKE SURE that fuse box has clean uncorroded fuses.Use brass fuses...not aluminum...be sure that fuse holder ears are super clean...many problems related all systems can be traced to dirty corroded fuses.
      You may have to get into the fuel distributor...under the intake manifold..NOT A EASY JOB...sorry to say.Check to be sure that big rubber bellows is without any holes or other problems....like it blew off when it had a back-fire...with the bellows(my words) off..lift the round flapper valve in the center of the fuel dist.with the key ON lift the flapper valve and listen to the fuel injectors pump fuel as the flapper is lifted....you may have to remove spark plugs to dry out cylinders.Sometimes a piece of grit stops the valve from moving freely...very important that there is NO resistance
in lifting the flapper valve....essentially the heart of the system..
         You must keep this area VERY CLEAN while working on this fuel injection part.
         In tank fuel pumps do fail and so does the feed hose that allows the intank pump to send fuel to the main pump.
          There are other possible reasons...my guess is the answer is here.
              Good luck,
                            Bilbo