49
Maintenance Instructions
REPLACING/REPAIRING
Fuel Filter
Model MB is equipped with an in-line fuel filter.
Visually inspect the filter periodically, and replace
the filter yearly.
Fuel Filter Location
IMPORTANT: Replace the fuel filter only in a clean
area where the fuel line and connections will not be
contaminated by any dust and dirt.
1.
Expand and slide clamps on either side of the
filter away from filter and pull fuel lines off filter.
2.
Replace filter.
Blade Overload Shear Bolts
The cutting blade is keyed to the blade hub by two
(2) shear bolts (10-24 x 5/8 in. stainless steel ma-
chine screws). These bolts are designed to shear
and protect the blade drive gearbox from damage if
the blade encounters a shock load.
Cutting Blade Shear Bolts
NOTE: Tightening the 5/8-18 blade mounting nut
to 60 ft-lb (81.3 N
·
m) is also important for proper
shock load protection. It is important to not over-
tighten the mounting nut since this defeats (over-
rides) the function of the shear bolts.
If these bolts shear, remove the blade and install
new bolts. Refer to CHECKING/SERVICING in this
section for Sharpen Mower Blades which describes
the blade removal and installation procedure.
After reinstalling the blade, check blade timing by
moving blades through one (1) complete revolu-
tion. Make sure blade tips pass clear of each other.
If timing is incorrect, contact your Walker Dealer.
PTO Shear Pin
The PTO drive shaft connection to the deck gearbox
has a shear pin to provide shock load protection to the
mower deck drive. This system provides primary
shock protection in case of blade impact and will
normally shear before the individual shear bolts on
the blade hub.
When the PTO pin has sheared, use the following
procedure to replace it:
1.
Loosen the two bolts securing the PTO shaft
guard on the deck; lift the guard off. (Holes in
guard are slotted for easy removal.)
DANGER
Gasoline is extremely flammable and can
be highly explosive. To minimize danger:
•
Use only an approved fuel container for
gasoline.
•
DO NOT allow open flames or sparks
near the machine while performing main-
tenance or refueling; DO NOT smoke
while working with fuel.
•
Wipe up spilled gasoline immediately
and completely.
In-Line
Fuel Filter
Cutting Blade
Shear Bolts
