L-100 won't start

Howdy all. I have a John Deere L-100 rider. It was given to me by a friend who said it was running fine then just stopped running while mowing. It will turn over but will not start. I noticed no fuel flow through the filter when attempting to start, so I replaced the fuel pump, filter and spark plug. Still nothing. What else should I check to locate the problem? Does a bad seat safety switch restrict fuel flow? Thanks in advance for any advice.

http://www.homedepot.com/catalog/pdfImages/fd/fd904936-46bd-471e-9536-7c3ca3698e81.pdf

check air filter for replacement, adjust valves engine cold per manual specs., check oil level on dipstick if it's high does it smell like gas? carburetor is possible problem, remove, disassemble, clean thoroughly with carburetor cleaner, fresh gas with quality fuel treatment per instructions on bottle. also check fuel tank for crud in bottom of tank, make sure gas tank cap vent is not stopped up. if you have gas in oil you will need carburetor overhaul kit, post B&S engine numbers from engine model xxxxxx, type xxxx, trim xx & code number.

http://www.greenpartstore.com/Model-L100_c_86-2-3.html

check fuse between ignition switch & starter relay, check all electrical connections by hand making sure they are tight & secure.
http://ww2.justanswer.com/uploads/K..._deere_l100_l110_l120_wiring_schematic_ii.jpg