Thank you for allowing me to assist you, my name is Joe and I will be happy to assist you with your concern today.
Please remove the spark plugs, ground the wires and crank over engine, let me know if at that time it then turns over fast and or has fuel shoot out of the engine while cranking.
These sometimes have a failing fuel solenoid on the fuel bowl that causes flooding of the cylinders which can lead to slow cranking and even complete hydrolock and thus is usually the first place I start looking. If the battery is not new or is but is from walmart or very cheap brand then please have it load tested to be sure it is good and is correct cca for that motor/machine.
It could also be a loose connection, high compression, weak starter, could be many things and thus after the above you may still find you need to reply back for further help.
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