Walker MDD (20.9 HP) - Manual (Page 69)

65
Maintenance Instructions CHECKING/SERVICING/
REPLACING/REPAIRING
Fuel Valve Open
(Engine START and RUN Position)
If the fuel valve solenoid is not operating properly,
the problem may be isolated by first checking the
operation of the solenoid as follows:
1. Disconnect the fuel valve solenoid wire plug
from the wire harness.
2. Make jumper wire connections from the sole-
noid to the battery:
a. Red wire to positive terminal (+), black wire
to ground (-).
b. Touch white wire to the positive terminal (+)
and the solenoid should pull closed (open
the fuel valve).
c. Remove the white wire and the solenoid
should hold the fuel valve open.
d. Remove the red wire and the solenoid
should open (close the fuel valve).
Replace the solenoid if it does not operate properly
by the above test. If it does operate, the problem is
in the electrical system and can be checked using
the wiring diagram. Refer to ELECTRICAL SYS-
TEM for Wiring Diagram in this section.
Blade Brake Action
Check the function of the cutter blade brake (and
blower brake on GHS models) by engaging the blade
clutch (PTO), operating the engine at full throttle, then
disengaging the clutch and measuring how quickly
the blades stop. Watch the rotation of the blade drive
shaft and blower pulley as a visual indication that
movement has stopped. If the brake is working
properly, all rotation will stop five (5) seconds af-
ter disengagement of the clutch. If the brake sys-
tem malfunctions - blades do not stop in five (5)
seconds - adjust or repair the brake before operating
the mower. Refer to ADJUSTMENTS of Blade
Clutch (PTO) in this section.
REPLACING/REPAIRING
IMPORTANT: ALWAYS use genuine factory re-
placement parts. Substitute parts CAN result in
product malfunction and possible injury to the oper-
ator and/or others.
Drive Belts
There are five (5) individual belts on GHS models
or four (4) belts on SD models:
•
Engine PTO Drive Belt (3 Groove Power Band)
•
Jackshaft Drive Belt
•
GHS Blower Drive Belt (GHS Model Only)
•
Hydrostatic Ground Drive Belt
•
Engine Fan Belt
The belts may be removed and replaced using the
procedures described on the following pages.
WARNING
It is important to check and maintain blade
brake action for safe operation of the ma-
chine.
Fuel Control Arm In
Open (Run) Position
Fuel Shut-Off
Valve
Throttle Control Arm (Noted For Reference)
DANGER
To prevent accidental starting of the en-
gine when replacing parts or repairing the
machine, remove the key from the ignition
switch and disconnect the electrical plug
on the fuel shut-off solenoid.