What can/are the causes for my 1600cc from idling as it won't idle unless I allow fuel to collect in the carb then it'll run but as soon as I use the accelerator it'll just die?
Sparky is probably right.
Quick test is to remove the fuel pipe from the carb and put it in a clear bottle.
Get someone to crank the engine and look for the spurt of fuel. I think Ozzies immortal words on the subject were something like the "spurt" should be strong and should easily hit the side of the bottle. Anything resembling a dribble just isn't enough
Before you start spending money disconnect fuel pipe from pump to carb and see if you are getting a good flow of fuel. If so check to see if any blockage in pipe. If that OK take carb top off and float needle valve to see if any blockage. If you can with needle valve out use air line to blow from where valve screws in though to inlet pipe
Robert