Walker B18 Operator's Manual

52Maintenance Instructions CHECKING/SERVICINGTire PressureInflate tires to pressures shown below:Deck Caster Wheel = 20 PSI (137 kPa)Drive = 15 PSI (103 kPa)Tailwheel = 20 PSI (137 kPa)Wheel Nut TorqueCheck the eight (8) Drive Tire mounting nuts. Every100 hours they should each be torqued to75 to 85 lb·ft (102 to 115 N·m).Sharpen Mower BladesCheck mower blade(s) for straightness, sharp-ness, condition of the cutting edge, and balanceevery 10 hours of operation (or more often whenmowing abrasive type grass or operating on sandysoils). Replace blades if worn, bent, cracked, orotherwise damaged (refer to REPLACING/RE-PAIRING the Mower Blades in this section). Usethe following procedure to check and sharpenblades:NOTE: Keep blades sharp - cutting with dullblades not only yields a poor mowing job but slowsthe cutting speed of the mower and causes extrawear on the engine and blade drive by pulling hard.1. Stop the engine, remove ignition key, and dis-connect the spark plug wires before raising themower deck to service blades.2. Raise the deck and secure it in the TILT-UPpo sition (refer to Deck Secured in TILT-UP Po-sition photo in CLEANING of Grass Buildupin Mower Deck Housing in this section).DANGERNEVER operate cutter blades with thedeck in the raised position.NOTE: PTO shaft must be disconnected be-fore checking blades for straightness.3. Check the blades for straightness by markingthe blade tip position inside the deck housing,and then rotating the opposite end of the bladeto the same position and comparing. If the dif-ference in blade tip track is more than 1/8 in.(3 mm), the blade is bent and should be re-placed.WARNINGDO NOT try to straighten a blade that isbent. NEVER weld a broken or crackedblade. ALWAYS replace with a new bladeto assure safety.4. If the blade cutting edge is dull or nicked, itshould be sharpened. Remove blades forsharpening by grasping the end of the blade us-ing a rag or a thick, padded glove, while loosen-ing and removing the nut, lock washer, and flatwasher that mounts the blade.5. Grind cutting edge at the same bevel as theoriginal. Sharpen only the top of the cuttingedge to maintain sharpness.NOTE: Blades can be sharpened with an elec-tric blade sharpener, conventional electric grind-er, or a hand file.CAUTIONALWAYS wear eye protection and gloveswhen sharpening a blade.WingTipDo Not Grind orSharpen on UndersideIntersectionWear AreaSharpen atOriginal 30° Angle30°Mower Blade Profile for Sharpening6. Check blade balance by positioning the bladehorizontally on a blade balancer or use a nailor shaft through the center hole. If either end ofthe blade rotates downward, grind (remove)metal on that end until the blade will balance.The blade is properly balanced when neitherend drops. Balance of a blade is generallymaintained by removing an equal amount ofmaterial from each end of the blade whensharpening.