engine won't start (used to...)

[hplacecf]

hi.

need help with 'engine not starting' issue.

1979 Chevrolet pickup. project truck (not driven on the road yet).
8 cyl engine 350.
4 barrel carb (I think quad-jet).
all looks original.

it started and ran fine last autumn, and the year prior to that - it never had any starting issues of any kind.
I started it a couple of times over the winter - no issues.
this spring I started it up and it ran fine - but after running about 10 minutes it stalled.
I have not been able to start the engine since.

I tried 'starting fluid'.
when I use starting fluid the engine DOES start and runs for a couple of seconds until it uses up the starter fluid. it does this every time, so the engine 'can' start and run.

made we wonder if it was getting fuel.

a couple of days later (after letting it sit without trying to start it) I disconnected the fuel line from the carb, replaced the fuel filter (since I was in there anyway, and as a test - new fuel filter would be 'dry').

I cranked the engine - without starting fluid - and it still would not start.
I then disconnected the fuel line again and found that there was now fuel in there, and the new fuel filter (that I had just put in there 'dry') was saturated and 'wet' with fuel. so, it appears that fuel is getting to the carb.

any ideas on what I might check next?

thanks