1978 Midget-water choke-just installed Weber Dvg. Have the manifold on tight,had to grind off part of exhaust manifold. Questions: 1.It starts up hard-the starter stops turning after a few seconds-If I keep trying it will start.(too much gas?) It runs great -at first-then dies at idle and will not take gas. It runs great at 2000++ rmp good power. What is this,-fuel pressure(stock mechanical pump-new), choke? thanks Jim