Small Engines (Lawn Mowers, etc.): lawn mower willnot start, fuel delivery system, professional repair shop

Question
i have a 6.75hp craftsman lawnmower model no 917.377593,i have rep;aced spark plug,filter and fresh gas,it still will not start,what is the next step

Bob

Answer
Bob,

  There are several reasons a mower refuses to start but the basic ones you have covered the not so basic are the following:
1. Remove the spark Plug and lay it on a bolt with the lead attached pull the cord and see if you have a blue to light white spark ask someone to help you If you have a blue and white spark then your firing correctly if there is no spark you need to take it to a repair shop for a new Ignition installation usually costing about $25-$70 depending on your location in the USA.
2. Are you getting fuel into the Cylinder?
Pull your Plug Prime the Bulb if applicable and try to pull the cord a few times another hand helps here have them place their finger over the plug hole to both check for fuel delivery and compression fuel will generally smell prominently on the finger where compression will be air suctioning inwards and blowing outwards if you have Both then most likely your in need of a tune up in which #1 comes into play
#3 If your not getting good compression or fuel delivery I would urge you to see a professional repair shop to have them make the necessary repairs.
#4 When you store your Mower during winter months sometimes the fuel does build up a lacquer in the Carburator a treatment of a small amount just a capfull of Fuel Injector and Carb Cleaner to a full tank of fres gasoline will help loosen up the deposits and keep your fuel delivery system in top mode always run it thru your mower completely before storing it
I Hope this helps you with getting your mower back to working for you