Engine Cooling System; Radiator Screen And Cooling Fins - Walker D21d Operator's Manual

Maintenance Instructions
6. Without removing, visually inspect the condition
of the safety filter for damage or holes. The
safety filter should only be removed for yearly
replacement (or when dirty or damaged).
IMPORTANT: Prior to removing the safety filter,
make sure the inside surface of the air cleaner
canister is clean. This will minimize the risk of
dirt entering the outlet tube which can cause pre­
mature engine wear.
7. After removing the safety filter, use a clean,
damp cloth and wipe the interior of the air clean­
er canister clean. Use special care to clean
both the inside and outside surfaces of the
outlet tube.
IMPORTANT: Any dust left on the inside of the
outlet tube will go into the engine and cause
wear.
8. Check the outside surface of the outlet tube for
smoothness and cleanness (this is the sealing
surface).
9. Insert and seat the safety filter and primary filter
element carefully into the canister, applying
pressure at the outer rim of the filter; not at the
flexible center. Make sure the filter element is
completely in place before installing the cover.
IMPORTANT: DO NOT use the cover latches
to force the filter into the canister–the cover
should fit on with no extra force.
NOTE: DO NOT use petroleum based lubri-
cants on the sealing surfaces of the filter; use
tal cum powder or dry silicone lubricants if re­
quired for filter installation.
Outlet Tube
Canister
Safety Filter
Air Filter Element Replacement
Primary
Filter Element
Radial Sealing
Surface
10. Install the cover with the word "TOP" properly
oriented to the top of the canister. Give the
cover a slight twist as it reaches the canister to
make sure the tab inside the cover goes into a
slot, otherwise the cover will not fit properly.
Make sure both the top and bottom cover
latches are securing the cover in place.
Cover Latch
Dust Ejection
Valve
Proper Orientation of Air Cleaner Cover
11. Check the air intake hose for cuts, nicks, cracks,
etc., and the hose clamps for tightness.
12. Reset the air filter restriction gauge (press but­
ton on the end of the indicator).

Engine Cooling System

Radiator Screen and Cooling Fins

To prevent the engine from overheating and possi­
ble engine damage, clean grass clippings, chaff,
and dirt from the fine mesh radiator intake screen
daily. In certain mowing conditions (dry grass,
leaves, tree "cotton", etc.), it may be necessary to
check and clean the screen several times during use
to prevent engine overheating.
1. Lift to remove the screen. To clean the screen,
wash with soapy water or blow out with com­
pressed air.
2. Inspect the radiator cooling fins for material
lodged in this area which would restrict cooling
airflow. Use pressurized air or water to clean.
DO NOT use any tool, like a screwdriver or
knife, to clean material out of the fins as this
may damage the cooling fins. DO NOT use cold
water on a hot radiator.
CLEANING
Orient to Top
of Canister
Cover Latch
67