Walker MDD (20.9 HP) - Manual (Page 86)

Maintenance Instructions
ADJUSTMENTS
82
IMPORTANT: The solenoid linkage should be
checked and adjusted any time the solenoid is re-
moved and replaced (either reinstalling an existing
solenoid or installing a new replacement).
Check and adjust the solenoid linkage as follows:
1. Manually pull the fuel valve open and check the
gap between the control arm on the injector
pump and the stop. The required gap is approx-
imately 1/16 in. (1.6 mm).
Fuel Valve Solenoid Linkage Adjustment
(shown with air intake hose removed for clarity)
2. If the gap is incorrect, adjust the linkage by
loosening the jam nut at the solenoid, remov-
ing the cotter pin and washer from the connec-
tion to the fuel valve control arm, and screwing
the linkage rod in or out of the solenoid as re-
quired.
3. After adjusting the linkage for the proper gap,
turn the ignition key ON, and check the gap by
operating the solenoid.
GHS “Full” Signal Horn with Grass-Pak
®
Switch
If the GHS “full” signal horn is not sounding when the
catcher is full, the following troubleshooting instruc-
tions apply:
Troubleshooting (When Horn Fails to Operate)
1. Check the horn.
a. Disconnect the two wires from the Grass-
Pak
® switch electric connector plug and
make a jumper wire connection between
these wires (bypassing switch).
b. Turn the ignition switch ON and move the
blade clutch to the ENGAGED position
(engine not running) to make the horn
sound.
c. If the horn does not sound, the horn is bad
and needs to be replaced.
d. If the horn does sound, proceed to step 2.
2. Check the Grass-Pak
®
switch.
a. Reconnect the wires to the Grass-Pak
®
switch electric connector plug.
b. Turn the ignition switch ON and move the
blade clutch to the ENGAGED position
(engine not running).
c. Open the catcher back door and trigger the
Grass-Pak
® vane by hand as it oscillates.
d. The horn should sound as the switch is
moved in both directions. If the horn does
not sound, the switch is bad and needs to
be replaced.
Checking the Grass-Pak
®
Switch
1/16 in. (1.6 mm) Gap
Solenoid Linkage
Rod and Jam Nut
Control Valve
Stop
Fuel Valve Control Arm
in Open (Run) Position
WARNING
DO NOT test the Grass-Pak
®
switch with
the engine running. Projectiles CAN be
thrown out of the grass delivery spout and
CAN cause serious injury to bystanders or
property damage.
Grass-Pak
®
Vane Switch