Start problem.Items checked &found ok,ignition,spark plug, carb, fuel tank cleaned , fresh fuel, is there a easy start i notice a momentry exhaust lift on the compression stroke, The engine fitted is SUMEC-LINHAI 150SV .
The engine you have is a Chinese Honda clone, and I would bet money that the ignition coil is duff. Usually, they spark in open air, but fail under compression.
Tecumseh coils can be modified to fit, are plentiful, and last longer than the rest of the engine.
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