My 79 MGB acts like it's not getting fuel. If I put fuel in the line between the filter and the carb it will run for a minute or two.
Replace the fuel filter and check the fuel lines between tank and pump, they might be obstructed after 33 years.
It is quite common for the contacts on the fuel pump to stick if left for a time. This is true even of brand new pumps. Can you hear the pump ticking when the ignition is turned on? If not, try hitting the pump with a suitable object (I always kept a hefty spanner in my MGB for such purposes) and it should start up.
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