Remove the spark plug from engine.
Replace badly fouled spark plug
Step
The tip should be clean and clear so that the spark travels cleanly to the tip.
Step
3Wipe away the dirt, oil gas and other debris with a rag. If you can
remove this easily, then you might be able to save the spark plug.
However if the corrosion stays on the spark plug, then it is truly
fouled and needs to be replaced.
Gap 49cc Spark plug Torch BM6A
Set plug gap 0.6-0.7mm
Replace plug