MTD 420 Series Lawn Mower User Manual


 
10
5
Maintaining
Your Lawn
Mower
WARNING
Always stop engine,
disconnect spark
plug, and ground
against engine before
performing and type
of maintenance on
the mower.
IMPORTANT: Do not use a
pressure washer or garden
hose to clean your unit.
These may cause damage
to electric components,
spindles, pulleys, bear-
ings, or the engine. The
use of water will result in
shortened life and reduce
serviceability.
Figure 5-1: Areas to lubricate on the mower.
General Recommendations
Always observe safety rules when performing
any type of maintenance.
The warranty on this lawn mower does not cover
items that have been subjected to operator abuse
or negligence. To receive full value from warranty,
operator must maintain the lawn mower as
instructed here.
Changing of engine-governed speed will void
engine warranty.
All adjustments should be checked at least once
each season.
Periodically check all fasteners and make sure these
are tight.
WARNING: Always stop engine, disconnect
spark plug, and ground against engine
before cleaning, lubricating, or performing any type
of maintenance.
Lubrication
Lubricate pivot points on the blade control at least
once a season with light oil. The blade control must
operate freely in both directions. See Figure 5-1.
Lubricate the wheels at least once a season with
light oil (or motor oil). If wheels are removed for any
reason, lubricate surface of the pivot arm and inner
surface of the wheel with light oil. See Figure 5-1.
Lubricate the torsion spring and pivot point on the rear
discharge door periodically with light oil to prevent
rust. See Figure 5-1.
Follow the accompanying engine manual for engine
lubrication schedule and instructions.
Deck Care
WARNING: Never tip the mower more than
90º in any direction and do not leave the
mower tipped for any length of time. Oil can drain
into the upper part of the engine causing a starting
problem.
Clean underside of the mower deck after each use to
prevent build-up of grass clippings or other debris.
1. Disconnect spark plug wire. Drain gasoline from lawn
mower, or place a piece of plastic under the gas cap.
2. Tip mower so that it rests on the housing. Keep the
side with the air cleaner facing up. Hold mower firmly.
3. Scrape and clean the underside of the deck with a
suitable tool. Do not spray with water.
4. Put the mower back on its wheels on the ground. If
you had put plastic under the gas cap earlier, make
sure to remove it now.
Engine Care
A list of key engine maintenance jobs required for good
performance by the mower is given below. Follow the
accompanying engine manual for a detailed list and
instructions.
Maintain oil level as instructed in engine manual.
Service air cleaner every 25 hours under normal
conditions. Clean every few hours under extremely
dusty conditions. Poor engine performance and
flooding usually indicates that the air cleaner should
be serviced. To service the air cleaner, refer to the
engine manual.
Clean spark plug and reset the gap once a season.
Spark plug replacement is recommended at the start
of each mowing season. Check engine manual for
correct plug type and gap specifications.
Clean engine regularly with a cloth or brush. Keep the
cooling system (blower housing area) clean to permit
proper air circulation. Remove all grass, dirt and
combustible debris from muffler area.
NOTE: This Operator’s
Manual covers several
models. Lawn Mower
features vary by
model. Not all features
discussed (or engines
pictured) in this manual
are applicable to all
Lawn Mower models.