In this country a product called Stabil is probably the most popular for fuel storage. Another is SeaFoam which is also used regularly in the fuel as a fuel system cleaner. In high concentrations it is excellent for de-carboning procedures. SeaFoam is also available in spray can form called Deep Creep.
if its a two stroke and the carbs are already clogged odds are you will pop a piston long before any "cleaner" will do anything. stabilizers will only last about 6 months and then only to fresh fuel. if the fuel is sour its trash, chunk it or be prepared for the results.
no the carbs arnt clogged ,i am just doing a service and thought it might clean the carbs[quick fix]and i have 5 gallons of fuel[i will ditch it[ thanks
