What have I brought ?

Hi I'm a new bee Went to a show and saw one of these and thought gotta get one So

I have a Petter stationary petrol engine Wico Type A 1057B Z Serial No E 553458

On the brass plaque It states Type A1

Not started it yet as stood for a year or 3 :-( Looks like petrol not getting to the spark plug If I tip some petrol in the plug hole it pops once and that's it Spark looks ok What should I do next ?