72 Chevy k20 350 won't start

[old Chevy guy]

Is it popping through the carb? You said something a ways back about it ticking or haveing a rocker noise. could have a bad cam and has an exhaust valve that isint opening. Ive had pushrods that pluged up. That how the oil gets up to the top and lubes the rockers. So the pushrod plugged and no oil came up and the top of the pushrod wore out and sounded like the cam was bad cause the pushrod was too short. Actually had that happen twice on 2 diffrent motors. Diffrent pushrod and rocker arm fixed it. Not saying thats it but something else to look at. Is it ticking now when running