Change the oil,sae 30.renew the spark plug,air filter.renew the gaskets on the carb to engine flange.replace the carb diaphrapm.clean and grease all control cbl's.check valve clearences.flush and clean fuel tank and check one way valves/filters.and check engine running speeds.I also usually check compressions.This covers only engine and the common points of failure on these .
caine, August 2008