Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Do a cylinder balance test. Loosen the spark plug wires, and with engine idling, remove one wire at a time. Engine should continue to run. If engine dies when either wire is removed, the opposite cylinder is not firing. If that is the case, check for spark and compression. If it has spark and compression, and is not firing, check the valve pushrods.
Did you run the test?
Did you check the valve lash while you had rocker cover off? 004 to .006 inch intake and exhaust.
you may have a bad diode in the kill wire harness between the tow coils! Remove the kill wire from both coils and see if engine run correctly. I don't see this as carb or fuel pump problem.
Good job I guess the two jets in the carburetor were the problem! Thanks for the reply! At least the balvance test got you headed in the right direction! Please rate to close.