If you are certain the spark plug(s) is in good condition and correctly gapped, and the magneto is working normally, then you may have a fuel system problem. A quick diagnosis of fuel system issues is to spray a shot of starter fluid or WD-40 into the intake through the throttle body. If the engine fires for a bit then quits, it's a fuel system issue. Small engines do not do well with old ethanol-containing fuel. If it's turned yellow, drain it out and replace it, and remove any in the carburetor float bowl also.
Air leaks in the carburetor or intake manifold gasket may also cause hard starting. A sticky carburetor float or float valve is another possibility, especially if the engine was sitting for a long time with ethanol fuel drying out in the float bowl. A dirty air filter will also cause starting issues.
I don't want to tell you something you already know, but you didn't mention that you tried your choke and whether it closes the inlet to the carburetor.
Check the unit for spark, I use a new spark plug and just disconnect the plug wire from the one installed and ground the new one to the head or block and then crank it over to see if it has blue/white spark at the plug electrode. If not make sure the kill switch/circuit is functioning properly. Check the spark coil leads to make sure the wires are intact. I would also check to make sure voltage is present to the cdi pack and that the wires are secure.
I'm not sure but it might be the sensor on the right front wheel disk
drain plug for what???? there is one for the oil under oil reservoir and you also have to drain the block too.as all the oil is not just in the block.
Sound like the needle and seat are dirty. Also check the fuel strainer / filter for debris. Usually if the needle and seat are dirty so is the filter / strainer & bowl.
Needle and seat item(s) 24 and 24 original factory Parts manual under carb. at the dealer:
(called float valve in description)
Sounds like the float valve is either not closing or is dirty and not allowing carb to fill to the proper level. i.e causes fuel starvation AND carb over filling intermittently. You can clean the needle and still have a bad seat for the needle.
Find and replace or clean the fuel filter also. If your carb has a manifold and nut on the side of it for the fuel manifold remove the nut (actually a bolt type thing) and clean the strainer inside the manifold.
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