Got a '78 350 in my Jag. Was running until I think when the gas ran out, so it sucked up crap from the olllld tank. I get stuff is going to be clogged.

Replaced fuel filter which was really old and dirty. Took off the Holley 4160 carb and replaced some of the gaskets (this is my first time working on a carb so I have limited knowledge). Didn't see any passages blocked but I sprayed the hell out of it with carb cleaner.

Fuel pump works, theres gas in there now, I have compression and spark (cos it was running until very recently.) I even replaced the plugs just in case. Distributor looks fine.

I'm a broke student so I have limited funds, quickly running out of patience too.

It won't start on its own unless I spray some cleaner into it, then it starts for a second or 2 and dies.

Think its just a passage thats blocked or what?

 

It's been a long time but, I would first make sure fuel is getting to the carb. Take off the fuel line connection to the carb, insert the end into a plastic bottle or cup. Have someone give the engine a quick crank. If fuel is there, some carbs have a small filter just inside where the fuel line fits. Change if there is one. Good luck.

 

Just curious, since the pickup sock inside the tank sucks gas off the bottom, what "crap" would be settled down there that wouldn't otherwise be there if you had a little more gas in the tank? Does going from say 1/8 tank down to almost empty make sediment mysteriously appear?
When you do a prime and it quits, can you see gas squirting down the throat of the carb if you pump it by hand?

 

is the fuel getting to the carb?