Walker MDD (20.9 HP) Lawn Mower User Manual


 
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Maintenance Instructions CHECKING/SERVICING
Charging the Battery
Check the battery charge by measuring the specific
gravity of electrolyte; if specific gravity is less than
1.225, the battery will need to be charged as follows:
1. Charge the battery at 15 amps for 10 minutes.
DO NOT exceed 20 amps maximum recom-
mended charging rate. Charge until specific
gravity is at least 1.250. Total charging time
should not exceed one (1) hour.
2. After charging the battery, use drinking water to
adjust the electrolyte level to the bottom of the
vent wells [1/4 to 1/2 in. (6 to 13 mm) above the
plates].
Tire Pressure
Inflate tires to pressures shown below:
Deck Caster Wheel = 20 PSI (137 kPa)
Drive = 15 PSI (103 kPa)
Rear = 20 PSI (137 kPa)
Sharpen Mower Blades
Check mower blade(s) for straightness, sharp-
ness, condition of the cutting edge, and balance
every 10 hours of operation (or more often when
mowing abrasive type grass or operating on sandy
soils). Replace blades if worn, bent, cracked, or
otherwise damaged (refer to REPLACING/RE-
PAIRING the Mower Blades in this section). Use the
following procedure to check and sharpen blades:
NOTE: Keep blades sharp - cutting with dull
blades not only yields a poor mowing job but
slows the cutting speed of the mower and caus-
es extra wear on the engine and blade drive by
pulling hard.
1. Stop the engine, remove ignition key, and dis-
connect the electrical plug on the fuel shut-off
solenoid before raising the mower deck to ser-
vice blades.
2. Raise the deck and secure it in the TILT-UP po-
sition. Refer to CLEANING the Grass Buildup
in Mower Housing in this section for deck rais-
ing instructions.
3. Check the blades for straightness by marking
the blade tip position inside the deck housing,
and then rotating the opposite end of the blade
to 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.
4. If the blade cutting edge is dull or nicked, it
should be sharpened. Remove blades for
sharpening 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 flat
washer that mounts the blade.
5. Grind cutting edge at the same bevel as the
original. Sharpen only the top of the cutting
edge to maintain sharpness.
DANGER
BATTERIES PRODUCE EXPLOSIVE
GASES
Charge the battery in a well-ventilated
area, so that gases produced while charg-
ing can dissipate.
Keep sparks, flames, and smoking ma-
terials away from the battery at all times.
Make sure the battery cap vents are open
(check manifold vent on each cap).
Make sure the battery charger is un-
plugged before connecting or discon-
necting cables to the battery.
DANGER
NEVER operate cutter blades with the
deck in the raised position.
WARNING
DO NOT try to straighten a blade that is
bent. NEVER weld a broken or cracked
blade. ALWAYS replace with a new blade
to assure safety.