11-01-17, 08:24 PM
ECU failures are very rare and - to the best of my knowledge - it wouldn't start at all if the ECU were faulty. Don't discount it completely but equally, don't jump to that conclusion right now. 
You say the fuel pump is running when you're attempting to start. Do you mean just the usual few clicks when you first turn on the ignition, or is the pump constantly trying to prime the carbs? If it's the latter, it shouldn't do that ... once the float bowls are up to the correct level, the pump should shut down until the fuel level drops.
Have you checked to see if you have a spark when attempting to restart after the initial start-stop-won't start sequence you described? If you have a decent spark, it would point to a fuel issue.
When you say it starts then dies, do you mean the revs gradually decay until it stalls out? Or does it just stop dead?
You say the fuel pump is running when you're attempting to start. Do you mean just the usual few clicks when you first turn on the ignition, or is the pump constantly trying to prime the carbs? If it's the latter, it shouldn't do that ... once the float bowls are up to the correct level, the pump should shut down until the fuel level drops.
Have you checked to see if you have a spark when attempting to restart after the initial start-stop-won't start sequence you described? If you have a decent spark, it would point to a fuel issue.
When you say it starts then dies, do you mean the revs gradually decay until it stalls out? Or does it just stop dead?