Briggs & Stratton MB (18 HP) Fuel Filter Location, Cutting Blade Shear Bolts, PTO Shear Pin

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.

In-Line

Fuel Filter

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.

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.

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

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.)

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