What is the valve setting on 5.5 hp. GoKart engine. I’ve read it’s a “Chonda” engine. I can’t get it to start. Read somewhere spark plug at .020 and air gap with business card. And valves at .004 intake, .006 exhaust. I can’t get any compression gauge reading with my snap-on tester. Two weeks ago it would start and idle but to try to advance the engine speed it would labor knock loudly twice and go dead. Would restart 2-3 times with same result. Help