I'm not sure if your carby has an anti deiseling valve but if is does this can cause problems and cause the engine to cut out. Check there is power at the valve when the ignition is turned on. But as dd said there could be few things to cause this problem.
I agree with Townie, Check that there wasnt a water hose conected to the engine breather. It's the steel pipe that comes out on L/H side (manifold side) of the block towards the rear.
DATUTE1 might know something. Copied from one of Dattosan,s posts.
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