Type 4 Engine Woes

[mole]

Having problems with fuel getting into the engine.The carbs have been off (Solex) and for the best part of it are in pretty good shape,changed a leaky float,replaced the fuel diaphrams.There is an electric fuel pump ,so have put a regulator on,the electromagnetic idle cut off valves were dodgy so sent off for new(thought that was the problem...bingo),however the left carb's threads are a little worn so have put a solid state idle valve in.Usual service parts done and valve clearances (thanks Loxy).Had it tuned and everything reads ok on the old diagnostic read out, apart from unburnt fuel.Checked the oil and still smells of fuel.Tune up man says give it a run there may be fuel within the exhaust system...Any suggsetions,advice as I'm really fed up now...nice van sat there doing jack s**t..............Thanks Mole..