We have a 3 year old Toro GTS personal speed mower. When it starts up the engine speed will alternate bewteen very fast/skow and then quit. I am *totally* ignorant about engines but it seems that the spring that controls the throttle is the problem. If we play with the spring it will run for a little while, but then stops again.
your carberator is dirty probably from gas left in it over the winter or the gas can that you use is contaminated
check your gas can and clean the carb and replace any gaskets when doing so. also for winter storage drain the gas out of the mower then run it till it stops. Doing this will get rid of any gas that will "rot" over the winter
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