It would not be the bar oil, unless maybe you put the bar oil in the fuel tank ;). I assume you have fuel in it, because quickly it would not start at all. There are others on here that are way better than me at small engine diagnosis than me.

Usually when a saw suddenly stops it fuel or ignition related providing you've done regular maintenance on it. Like clean or change the air filter, fuel filter and keep fresh gas in it. When it don't start try to find out whether it's a fuel starvation problem or an ingition problem.

You can check the fuel starvation problem by using carb. cleaner, spray a short 2 second blast into the carb. opening the little hole called Venturi, turn the ingition on and pull the rope. if it fires off the carb. cleaner then I good change it's not getting fuel to or through the carb. naturally you would want to check the fuel filter first, especially if you haven't changed in a long while.

to figure out if the ignition system firing, remove the plug plug it back into the spark plug wire lay the metal part of the spark plug on the metal head of the saw, turn the ignition on and pull the rope, you should see a pretty blue spark.

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john

Do what was stated above. I would first start by using fresh gas. Next I would change the fuel filter and clean the spark plug. I'd also check it for a spark. I'm willing to bet you have a fuel problem. As your replacing the fuel filter, check the fuel lines for cracks. If your getting a spark, then time to clean the carb. If doesn't take much to plug a carb on these 2 stokes, but removing the carb and cleaning it with carb cleaner will help. If your saw runs for few mintues than shuts off once its warm, your ignition is most likely the problem.