L21zsn will not start.

[mcostello]

It has spark, and compression. If I spray starting fluid into the carb, no joy. Changed the plug several times. Hints, suggestions, or a friendly tap on the shoulder to wake up and see the trees not the forrest.

 

[Rivets]

Are you sure that the engine is not flooded? These 2-cycle engines like to have an accumulation of fuel in th crankcase when the user keeps priming, resulting in a flooding condition. Maybe this manual will help you out. Comeback with more specific questions. https://www.lawnboy.com/getpub/6930

 

[mcostello]

I cannot get a "wet" plug. I have cleaned the tank and all hoses and fuel shut off valve. Gas flows from the hose when disconnected from carb. Fuel bowl has fuel in it. Will give it a few pulls to clean it out with the plug out. Last it ran, it was running fine then the mag died. I have had to buy and return 2 mags before finding one that had some spark. Good spark when testing outside of engine.

 

[Rivets]

How can you test a magneto outside the engine? Today’s magnetos use a Hall Effect trigger which can only be tested with a very expensive piece of equipment. If the plug is dry and you are sure it is firing when installed and you are sure that fuel is not getting to the cylinder, I suspect you may have a bad crankcase seal which is not allowing fuel to get from the carb into the crankcase.

 

[mcostello]

Engine holds vacuum well, have not checked pressure yet.